Thursday, April 10, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 18

Audio Recording Issues – Multiple Microphones Setup to Track the Same Instrument and Need the Right Balancing Together Part Two

Balancing the drums is about the volume levels in comparison to the mix, but it is also about balancing the top and bottom head microphones of each drum if using both. You may have more of certain drums captured in overheads and room mics than the others.
Once you are mixing and blending things together, you may find a more intricate process developing. Let's say that the direct mic blend for the snare is perfect when it reaches a certain volume, but it tends to have too much of a certain Frequency when you feed the overheads into the mix. Or, the complex stereo capture of the overheads are great for the whole set in the context of the mix, but they lean too heavy on certain Frequencies. The Equalization decisions may be very tricky. Each drum and each mic choice may have areas that take away from other instruments. Before you go carving away chunks of great tones, consider creating an order of preferences and levels of importance. You may find that some Frequencies are best to reduce from a track other than the drum or overheads, and in other situations you may find that some Frequencies appear to stand out because of positioning or even due to timing. Often, the small delays that build up from the distance of one mic to the next can create a Frequency that results from this distance between the two. It isn't always necessarily phase, as we usually call it. Sometimes, it is more about what I call the reach of the microphone more than the timing element.
Let's pretend that I set up two of the exact same mic to record a single drum sound. Both mics are in an omni mode. The first mic is placed one foot away from the drum and the second is ten feet back from mic number one, eleven feet from the drum. Once recorded, there is not only the difference in the sound of the instrument, but its effect on the walls around and the ceiling above and floor beneath. With both mics in omni mode, they are both picking up a lot of information from their surroundings. The sound is going to travel a distance before it reaches the second mic, but also in that time, the first mic has resounded across the room, so there is an initial attack from the drum, no doubt captured with more intensity and clarity by the first mic, and the wash over, or reflections of the room, whether small, short, tight or big, long and open. That second mic will hear a residual attack very shortly after, with a different resonance and a larger blend of the room, along with the resulting room sound that the hit creates and the blend of the room from a distance. We could align these two responses in time so that the later recording is brought forward to play at the same time as the closest mic, but this is not always the best decision.
Sometimes, the mic choices lead to a phase correlation issue that is best resolved by aligning the timing of mics. Other times, it is the distance itself that we want to measure in the sound. Still other times, the range of Frequencies can be complicated by the reach of the mic, meaning that the sound waves that develop in that distance are being captured by the distant mic and not just the alignment of the time, meaning that any change in distance and position can affect Frequencies that otherwise would not exist in reality. They are a combination of the sound created, the room reaction, but also an equation of the sound captured by mic one added to the sound captured by mic two, the result being additive and sometimes the results can cancel out some Frequencies and boost others, all the while responding largely accurate to the source and distance. In this case, we can adjust timing, which can have a negative affect on the timing between other instruments or drums, or we can reduce the residual bumps in the recording from one mic or the other, or a little bit of both.
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Thursday, April 3, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 17

Audio Recording Issues – Multiple Microphones Setup to Track the Same Instrument and Need the Right Balancing Together Part One


Learning how to Equalize Frequencies within a range of different contexts requires numerous skills and the ability to define one's style with cohesiveness. There is a single process that serves as a testing ground for a contextual series of abilities, all inclusive, and that is the process of recording a single instrument with multiple microphones.
The drumset is the perfect instrument to serve as an example for this common occurrence. Live drums have been successfully captured as part of an ensemble of instruments in a pleasant room with a single mono microphone, a perfectly positioned pair of matched stereo mic's, and with a 3-mic array. All of these techniques have been used with remarkable success and many engineers utilize these purist approaches with incredible results. More often than not, we find a more comprehensive approach taking place. Project studios may use very inexpensive dynamic mic's on the top heads only, with a pair of high quality but inexpensive cardioid condensers as overheads, and skip on the room mic's.
This same project studio may have an 8-input audio interface with decent built-in preamps employed. The high end studio aiming for the standard contemporary approach to recording a drumset may use similar dynamics on the toms and snare, on top and bottom heads, with a mic on either side of the kick drum and an expensive large diaphragm at a small distance on the kick, an expensive pencil condenser on the hi hat, a pair of room mic's, a pair of overheads, all running on boutique outboard preamps. Whether you are at the lowest budget production or at the world's finest facility, you are likely to be facing some of the same issues when it comes time to mix these drums together.
Let's fast forward and assume that we've tracked our drums and everything else in the song is ready to mix. Now, we've got to decide how this all comes together. Realize, it may be one thing to set all of those mic's up and compare levels, angles, positions, and everything else, to get the best capture of the set. Now, we have the challenge of deciding how loud the snare should be in comparison to the guitar and bass, and how much of that should come from the direct mic and how much from the overheads. Is the song calling for an open and ambient set or a tight, punchy, up-close set? Is the stereo spread and distance of the overheads consistent with the feel of the song or is it too complex sounding? Are you best to use the directs and supplement them with the natural reverb of a room and/or overheads, or vice versa? The approach to tracking and mixing largely define how the performance should be brought together. In part two, we'll take a look at how EQ helps us with this process in multiple ways.
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Monday, March 31, 2014

How to Mix and Master with EQ – CDSoundMaster.com – 12 EQ Issues Part 16

Audio Recording Issues – Nice sound when tracking, but way too much "-----" when blending parts together, Part Two


So, what happens when we get too much overlap of a given range of Frequencies? Obviously, it sounds wrong. The overall volume of a mix is compromised because it has to make room for a lot of a certain Frequency range, thus the other Frequencies are too low in comparison. Some people attempt to rectify a good mix that is too heavy in a given range by squeezing it flat with compression. This results in one of several bad endings. The mix may distort in reaction to an abundance of spectral tones, or we may get pumping and breathing from Frequencies that were fine otherwise. The point being, that if there is too much build-up in a certain range of Frequencies, they have to be dealt with before a good mix can happen. It is better to identify any conflicting tracks before mixing down, or the result will have to be dealt with at mastering, at which point other parts of the mix may be compromised that didn't have to be.

Why does this build-up tend to happen? As I mentioned in the previous post, sometimes it is the mere fact that multiple parts of the instrumentation or music performance involve instruments or vocalists that are in the same range as each other. This can also happen by using the same microphones and preamps over and over again. It is likely that some of your favorite “go-to” tools are not only the super-flat, super-precise ones, but often are chosen because of their personality. “I love the ----- for bass and the ----- for vocals, etc.” These choices can create intentional boosts and cuts in our mixes by preference, but come mix time, the same hills and valleys are already there. If we don't know when this is a good thing, we might end up doing some truly awful things to the mix.

Sometimes people have no reason to run into the issue until mix time, because of their routine mix practice. Some people like to use high or low pass filters on every track. They say that it cleans things up and always leads to a better mix. I understand the logic and agree that this process is logical and people that are successful with it have their reasons. It is a well planned process for selecting certain Frequencies to cut out of each portion of a mix, so that there is plenty of space for each instrument in the blending together of the mix. However, this can also be the first stage that a person realizes the over-use of other Frequencies, or there may have been better mixing options before removing certain sections of extreme spectral ranges, and now the focus brings rough central frequencies to the surface. I personally avoid using high/low pass on all tracks as a practice for one main reason: there is a lot of intricate timing information captured across all Frequencies. I tend to only change or eliminate things if I know I want the color, musical, or surgical result, and only if it is not sacrificing details that give the brain lots of feedback about timing, placement, distance, etc. But, regardless of what got you there, we are talking about the situation where nothing was a mistake, but there is simply too much x, y, or z happening. So, the toughest question: “what do you get rid of?” You like the balance and you like the individual sound. You don't really want to get rid of any of it, but the mix is simply too heavy on certain Frequencies. I recommend going to the center of the issue, which is to identify the bump.

“Huh? Identify the bump?” It is very likely that the overlap that is happening has a complex texture that is not all built up in a perfect slope across all of the exact same Frequencies. There are bound to be smaller patterns within the overall offending range. For instance, where an earlier example there was too much mid range coming from a lead vocalist, guitar, and tom tom section that were all awesome but sharing lots of mids, I recommend listening to only these elements and follow the rhythmic choices for the specific song. How often is each element running in unison? Which of these are more prominent? Is it possible to turn an instrument track down to lessen the load, or does it need to be up in the mix? Can you carve only one small part of each of them out to make room for the other? Although I will go into that in more detail with a future post, what I recommend is to think of this like the range of Frequencies that you are dealing with is a mountain. We are looking for the molehills, or to put it more accurately, we want to dig little chunks out of the least important sections within that mountain range.

Let's pretend the mountain starts at 500Hz, peaks at 2kHz, and recedes back down at 5kHz. This is not a consistent bell shape, but has the most build-up towards the middle Frequencies. The highest peak represents the Frequencies where the most overlap occurs between the multiple tracks. The greatest issue occurs from notes that sustain the longest, but if any notes stick out that are harsh or cause peaks that force the rest of the mix to a lower average than needed. The goal is to isolate how much to reduce, only from the Frequencies that overlap the most. You may want to only reduce a little of the guitar in one part of the range, a little from the vocal, and a little from the tom toms. This will lead to an overall reduction of the problem Frequencies without having to reduce them all the same amount, or to reduce any other parts of the mix by the same amount. You can also do a small amount of multi-band compression to slightly reduce the peaks in these areas, especially if any of the instruments are short notes instead of sustain. This allows short peaks to come into balance with less noticeable effect on the mix. The entire mix can increase by the resulting change. I have spent many years developing my own process of a more complex complementary Frequency process as well, but for the sake of staying on topic, let's stick with the effective process of reducing the bumps of Frequencies from combined sources by identifying them to their sources, and reducing them at the source, in order to make the mix smoother.

 

Wednesday, March 26, 2014

How to Mix and Master with EQ – CDSoundMaster.com – 12 EQ Issues Part 15

Audio Recording Issues – Nice sound when tracking, but way too much "-----" when blending parts together, Part One

In the past several posts, I have been writing about scenarios where you have a great sounding mix in progress and a great sounding track you just recorded, but the track doesn't work in the context of the mix. Now I want to discuss a similar scenario where this is happening across several tracks, or even across every track in the mix. I'm not necessarily talking about a situation where every track is completely wrong for the mix, as this would suggest something wrong in the technique, or maybe this song wasn't ready for recording at all. I am rather talking about the actual process in mixing where we are blending all of the creative elements together.

Whether it is at a stage of working with raw tracks, in the process of editing, or through the process of adding effects and making changes, that it seems as though tracks are simply not working well together. It is easy to run into issues during the tracking and mixing process that are simply not relevant until real mixing begins. Sometimes we are working under the pressure of time constraints and other times we have to play multiple roles, where we are thinking in terms of doing everything as an engineer to capture the best sound, and later flipping to the role of critical listening in the context of a mix.
 
Regardless of the reason, often we find that when it comes to balancing levels, panning, EQ'ing, adding compression, reverb and other effects, we run into a situation where the overall spectral balance is totally out of balance. How does this happen? You may have a very well-tuned room. You might choose great microphones and preamps and have the best singers and musicians with awesome equipment. You might even be using everything correctly. But, now that you are in the mode of serious, critical listener Mixing Engineer, you start to pile on the tracks and the Frequencies are simply not working well with each other. We often run into this with the “too much of a good thing” scenario, where the exact reason that everything seemed to go so well in tracking is now the downfall, as every layer is adding the same room elements, the same subtle boosts and cuts of microphone and preamp combinations, or it may not be anything technical to blame.

The chances are good that you have the same excellent sounding mid range Frequencies pounding the tom toms as you do screaming from the Marshall Cabs, and if the lead vocals are roaring through at the same notes as the rhythm guitar guy, then you are going to have a lot of mid range Frequencies in your mix. This might sound like it is ideal. Sure, just make sure the kick and bass guitar have some killer low Frequencies and the hi hat is spitting out a beautiful high end, and it should all come together, right? Well, the problem isn't necessarily about this kind of balance.

That sounds like the perfect imaginary land we have all pictured before reality sets in during session work. The truth of the matter is that every studio session that involves multi-tracking and mixdown has some element of surprise that will be dealt with in some unique manner. The way we react, the way we hear things, and the skills we acquire will be the parameters that affect the end result. This is where we put our signature to our sound in the mix.

CDS

Monday, March 24, 2014

How to Mix and Master with EQ – CDSoundMaster.com – 12 EQ Issues Part 14

Audio Recording Issues – It Sounds GREAT On Its Own, but... Part Five

Maybe it is a difference of room dimensions making it difficult to adjust a track properly within the context of a mix. Maybe it is a timing issue related to similar Frequencies. But, maybe it is about dynamics and distance. Along with the wonderful things that our brain does with sound interpretation, it pays close attention to where sound is coming from. The human ear, as limited as it is compared to what some animals can hear, is designed to send an incredible amount of information to our brain for approval. Complex timing elements are combined with location to tell us not only what we are hearing, but whether it is close to us or far away, to our left or right, and whether it is an obvious sound that we recognize or if it is very subtle and hard to identify.

In a mix, the context of these things work together for our approval or distaste. We may have a music track that is a little washy and distant, with a lead vocal that is extremely loud and dry. Some people like this; others don't. Usually, a good mix brings it all together in one form or another, but sometimes we intentionally bounce one character off of another to get a new response. What happens if a track is exactly what we want, but in the context of the mix, it sounds weak? We turn it up but now it is too loud. We turn it down where we think it belongs regarding volume, but it sounds weak. We solo the track, and it sounds perfect! Is it possible that we are dealing with a symptom of conflicting dynamics? What I mean is that we may have consistent performance levels from everything else in the song, or we may have already compressed other elements in a song individually, but the natural dynamics in our new track sink down too low in some parts of the arrangement and maybe sit just loud enough at other times.

If this is the case, we may be able to resolve the issue with a simple limiter. By raising the average volume up by a few decibels or reducing the peaks, we may get a consistent performance that sounds more full all of the time. What if we try that and now it is way too loud or sounds different than we want? Or, it just doesn't fix things? Sometimes, the reason comes back around to Frequency adjustment. Let's say that we have the example of another mix on the same album. Using the same approach, everything is great. So, why is it not working here?

You listen to tracks and suddenly you realize that one song is more up-beat than the other. Why should that matter so much if the process worked so well? Shouldn't that always be the case? It is possible that the performance is different from the working mix to the troublesome mix? This might mean that the drummer is tapping at the bell of the hi hat in the working mix, but is sizzling at the edge of the hi hat in this one. The change in performance can change the length of time it is resonating those powerful high Frequencies. You may have a beautiful EQ boosting the pristine recording of that hi hat in the same amount on both mixes, but this time around, the fact that it sustains for a long time instead of gentle taps, means that the Frequency just isn't available to your other track now. Having both tracks contribute to the same sound range makes for a busy neighborhood! You can try to select different Frequency options to get this under control, but the chances are that one change will lead to another and so forth, you find yourself changing elements that you used to be happy with. You might try lowering the hi hat volume, but it may make the rest of the drums sound unbalanced. What can you do?

Maybe you can try very small changes in the stereo field, making a little room for the hi hat just a tiny bit to the left or right. Or, you can try narrowing or widening the stereo field of just the track or the offending part of the mix so it gives a different location for the Frequencies to sit in the mix. Or, you can see if trading one high Frequency for another just on the track in question helps. All of these things are good ideas, but what if none of them work? You may consider a very small amount of several options. Try things I have mentioned that deal with timing, balance, dynamics, ambient rooms, Frequencies, and location. Try them in combination with each other and with different, small increments. Are any of these helping a little bit?

Most likely, some very small changes to multiple pieces of the equation will resolve the issue and help you to be pleased with that track once again. If that is not the case, you might actually be dealing with a case of “if you can't beat 'em, join 'em.” By this, I mean that you may need to incorporate that new track more into the room environment that the rest of the mix resides in, or vice versa. Is it possible that your new track is simply too dry and needs a tiny bit of reverb to get it to sit closer to the context of the song? Is it possible that the song sounds great dry but might work well with a tiny bit of the same kind of reverb that worked well for the new track?

Add these different elements together and see if some combination leads to a better result. I have a feeling that it will. There are plenty of other scenarios that affect the outcome of mixes, but this should give you an idea of some ways that tracks interact with each other and hopefully it can inspire you to spend that extra time listening and tweaking mixes that leave you less than inspired. I don't encourage you do overdo anything that is already mixed the way you like, but if you are left unimpressed with a mix, there are things you can do to potentially bring things to life that are not drastic, and leave very little changed from track to track.

CDSoundMaster.com

Wednesday, March 19, 2014

Audio Recording Issues – It Sounds GREAT On Its Own, but... Part Three

Our poor track. It sounds awesome, but either the rest of the mix is a bully, or it doesn't want to play fair. Before getting into a political topic of individualism versus collectivism (don't even get me started!), let's stick with a finite list of situations that we can identify as a root cause for mix injustice. It can be a timing issue. The song is not being mixed wrong, and the track is excellent, but we may be dealing with the way that the brain interprets sound signals. If we record something incredibly precise in a dry environment with very little character from the room, then we can get a recording that is amazingly present, in your face, intimate, and measuring somewhere between realistic and super-realistic. If we record something else that has some distance to it, then the complexity of the sound that bounces around in that environment will get measured in the context of the whole mix, and this may not be a good thing. One problem can be that when added, our brain says “nope, that isn't realistic.”

I don't mean to say that it is fake or bad sounding, but that the idea that a lot of sounds came from one place and another is from somewhere else that does not fit, can mean that a perfectly blended mix is not working from a completely conceptual, functional standpoint. If this is the intention, then obviously we don't need a solution. But, if you think the problem with balance is coming from two environments that do not belong together, then we may be on to something. But wait, what if there is some room presence, reverb, or liveliness that is making the new track conflict? Now what?

It may be possible to reduce only the part of the room's character that is feeding the majority of information to our brains. This can have multiple benefits, but some of it is covered in a later topic. We may be tricking our ears into re-interpreting tracks that we were happy with before, because those Frequencies that are the most obvious in carrying the room's qualities may also fluctuate in a different rate or pattern than they occur in the balance of the mix, so now our brain says “not only is it coming from a different location, but it carries information that doesn't fit into the groove of the song.”

Isolate your Frequencies with a narrow boost signal, control your output with a limiter for safety to your ears and monitors, and see if the issue is the most noticeable in the lows, mids, highs, or all of the above? Find the problem Frequencies, figure out the width of their “Q” if necessary, and reduce only the amount that reduces the complexity in the context of the mix. This means to solo the track and also check it with the mix, both while making adjustments all along. Did this help? Then, maybe the only problem was timing from the complexity of a room signal. Excellent! Did it help, but not enough? Likely so. Maybe we should see if there is something else going on here. I will cover these other possibilities in Part Four.

CDSoundMaster.com

Audio Recording Issues – It Sounds GREAT On Its Own, but... Part Four

Maybe the room was part of the issue in our track that won't work quite right in context. Maybe there are other timing issues as well. What if we are looking at the way we interpret timing as it relates to dynamics. What I mean here, is that there is the natural flow of the song, and there is the rate of expression that comes from each track in the song. You may have punch from drums and melody from bass and vocals, or you may have sustain on drums and cymbals and more rhythmic elements from percussion or busy bass and guitar. There are numerous things in the musical arrangement that affect our interpretation of sound. When we put it all together, there may be the wrong punch or sustain in Frequencies that otherwise sound wonderful. For example, a great vocal is intentionally recorded up close with a cardioid pattern large diaphragm condenser microphone.

The presence of the recording fills out the low Frequencies of an amazing vocal performance, we also have this incredible sustaining bass guitar with energetic sub-bass Frequencies that sit beautifully on top of a clean, clear, punchy kick drum. But now, the smooth low end of the vocal makes you reinterpret the perfect blend of sustain and punch that was there before. Should we reduce some of the bass on the bass guitar? Should we take a little out of the vocal and bass? Or maybe, a little compression on the vocal would serve well? Maybe the vocal compression should be grouped with the bass and kick? Perhaps this group compression could lock the timing together and re-orient our listening to hear these elements as a unified process?

This works sometimes, but usually we have more do deal with. I've found that often the simplest solution is also the best solution. I have developed a process that I will write about with more detail at a later time (would anyone read a full book if I wrote one?). I will mention it briefly here. Using a little low shelf EQ in this instance may be the perfect solution. You can use the same wide slope, like something found on the “Cooltec EQP-1A3S” or the “ARQ,” or you can try a combination of two different slopes, like the “115HD” for one instrument and the “AMK9098” for another.

The idea is to reduce a very small amount of a very wide Frequency range down to its lowest point so that we still feel the energy that is there, but it reduces the focus and allows us to concentrate on the other instruments in that range. What I add to this, is to listen to other mid and upper mid Frequencies on the same tracks and see if there is something that has a similar quality that impresses you the same way as the lows. For instance, the low may emphasize an incredible “pluck” of a pick on the bass guitar or the moody sustain of a vocal. Is there another place in the different Frequency registers that are complementing this trait? If so, there is a good chance that you can reduce the lows slightly for one instrument and boost a tiny amount somewhere else that gives the same energy but from a different range. A “pluck” may sound great in a fast attack at low Frequencies, but it may also give precise information in the upper mids, and we might re-orient the conflict from an offending Frequency to one that doesn't clash, and now we can have everything that sounded so nice without conflict.

Monday, March 17, 2014

How to Mix and Master with EQ – CDSoundMaster.com – 12 EQ Issues Part 12


Audio Recording Issues – It Sounds GREAT On Its Own, but... Part Three

Our poor track. It sounds awesome, but either the rest of the mix is a bully, or it doesn't want to play fair. Before getting into a political topic of individualism versus collectivism (don't even get me started!), let's stick with a finite list of situations that we can identify as a root cause for mix injustice. It can be a timing issue. The song is not being mixed wrong, and the track is excellent, but we may be dealing with the way that the brain interprets sound signals. If we record something incredibly precise in a dry environment with very little character from the room, then we can get a recording that is amazingly present, in your face, intimate, and measuring somewhere between realistic and super-realistic. If we record something else that has some distance to it, then the complexity of the sound that bounces around in that environment will get measured in the context of the whole mix, and this may not be a good thing. One problem can be that when added, our brain says “nope, that isn't realistic.”

I don't mean to say that it is fake or bad sounding, but that the idea that a lot of sounds came from one place and another is from somewhere else that does not fit, can mean that a perfectly blended mix is not working from a completely conceptual, functional standpoint. If this is the intention, then obviously we don't need a solution. But, if you think the problem with balance is coming from two environments that do not belong together, then we may be on to something. But wait, what if there is some room presence, reverb, or liveliness that is making the new track conflict? Now what?

It may be possible to reduce only the part of the room's character that is feeding the majority of information to our brains. This can have multiple benefits, but some of it is covered in a later topic. We may be tricking our ears into re-interpreting tracks that we were happy with before, because those Frequencies that are the most obvious in carrying the room's qualities may also fluctuate in a different rate or pattern than they occur in the balance of the mix, so now our brain says “not only is it coming from a different location, but it carries information that doesn't fit into the groove of the song.”

Isolate your Frequencies with a narrow boost signal, control your output with a limiter for safety to your ears and monitors, and see if the issue is the most noticeable in the lows, mids, highs, or all of the above? Find the problem Frequencies, figure out the width of their “Q” if necessary, and reduce only the amount that reduces the complexity in the context of the mix. This means to solo the track and also check it with the mix, both while making adjustments all along. Did this help? Then, maybe the only problem was timing from the complexity of a room signal. Excellent! Did it help, but not enough? Likely so. Maybe we should see if there is something else going on here. I will cover these other possibilities in Part Four.

CDSoundMaster.com

Wednesday, March 12, 2014

How to Mix and Master with EQ – CDSoundMaster.com – 12 EQ Issues Part 11

Audio Recording Issues – It Sounds GREAT On Its Own, but... Part Two

Our goal is to get an individual track working with the rest of its mix. We've identified that it was recorded and performed well, so this is not an issue of quality. Most often in the modern mixing scenario, we use a combination of limiting, compressing, EQ'ing, and effects to build the collection of sounds into an arrangement that accomplishes the final sonic goal. The issue of a track's success becomes contextual in place of individual merit. In this case, I am not talking specifically about an issue where you discover an imbalance of Frequencies in context, but rather we have a blending process that does not work.

My recommendation here is to identify the reason, or reasons. What is the context of the recording? Is it a tight, punchy radio hit, or is it about natural performance and room ambience? Is it about a strong lead vocal in front of a balanced music track, or about a band's sound having simultaneous impact? Is the track that you are struggling with not working because it sounds out of place, too quiet, too dynamic, off pitch, boring? You may have a combination of issues taking place. If you cannot identify what bothers you, you will be using random techniques to resolve the issue that may or may not work.

I know from experience that this process is not always as easy as we would like for it to be. Sometimes the problem is very subtle, and other times it results from various combined issues. It may be that a wonderful, elegant, smooth, rich, rounded low end Frequency sounds muddy once bringing things together. Or, the mere fact that something was recorded with an incredible spectral range is making other parts of the mix sound inferior in comparison. For example, you start with a great, punchy drumset, that is until you record one of the best rhythm guitar tracks ever, and all of a sudden the full range of energetic lows and screaming highs now make the drum heads sound papery, thin, and clicky. You didn't necessarily do anything wrong when recording the drums OR the guitar, but the end result doesn't measure up.

Monday, March 10, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 10


Audio Recording Issues – It Sounds GREAT On Its Own, but... Part One

How many times have you set up a great sounding microphone, plugged it in to one of your favorite preamps, set up your level, tested positioning, and recorded a wonderful sounding performance. You can't wait to get down to mixing. Despite the fact that you have done your job well, it is simply not coming together. Highlight any single track, and there is nothing you would change. Start adding things back in, and it simply is not coming together. I am breaking certain elements of this concept down into different topics because it is part of the complexity of mixing itself. When treating recording, mixing, and mastering as art forms just as much as a science, we find that there are vitally important interpretations of what makes an identifiably successful mix. For this reason, we see massive trends in what the listener considers high quality.
At one time, the trend leaned towards increasingly louder mixes.

Mixers and Mastering Engineers had to increasingly become experts in learning ways to trick one's perception into hearing "high fidelity" while simultaneously crushing the very life from mixes with extreme gain drive and compression techniques.

To address the topic of sounds that are on target in technique but are not working in context, I am writing here to address some reasons for this along with ideas to correct the issue. In following posts, I will write about how this is sometimes the result of having too much of a good thing, and in the specific issues of overlapping spectral balance. For this post, let's look at the fact that different recording techniques give unique results. If we are talking about the most complex aspect of tracking or recording, then we are looking at the source, microphone, preamp, and then the mix context. In slightly easier form, we are dealing with virtual instruments, loops, or samples, which provide source that is selected in the composition and mixing process, but recording and some processing decisions have already been made for us. Let's assume that we want to address the problem first at the source. Is the offending track recorded in the same environment as the rest of the mix or a different one? Is it recorded at a distance or closely? Is it extremely clean or does it have a lot of ambient sound? How these variables connect to other tracks in the mix can have a huge impact on what our brains are interpreting from what we hear.

Wednesday, March 5, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 9

Audio Recording Issues – Overtones That Overstay Their Welcome, Part Two

Now that we've addressed some of the potential scenarios that can come up in sessions that produce unwanted overtones, let's look at some EQ solutions that make the most sense.

The goal in properly addressing and resolving specific overtone issues is to play the offending track against the mix. This may be tricky, depending on what role the track plays in the prominence of the mix. Set up as many final elements in the mix as possible. I recommend slowly fading in the track you are operating, on and listen for the tonal issue. Does it come across like a specific Frequency or set of Frequencies, or does it tend to clash with legit notes from other instruments? Is it a wide range of Frequencies, narrow, or multiple? Usually, you can use a fairly standard bell shape to reduce the effect of the overtone. If it has the characteristic of a specific pitch, you may want to use a narrow EQ to reduce its effect.

Some overtones may be built into the fundamental notes, like a Hammond organ for example. The notes on a Hammond are controlled by multiple sliders, each controlling a different pitch, or harmonic order. Quite literally, the tonal character of the organ's sound is being controlled by adding or subtracting octaves to the fundamental. These may sound fantastic until final mix, where they resonate the wrong way compared to other notes. Usually, a medium "Q" can reduce the specific Frequency range where it gets into trouble.
Where Program Equalizers, like Pultec-type designs, are very effective for enhancing wide portions of sound, like the entire mid-range, specific low end or high end sweetening, they are not perfectly suited to the surgical elimination of overtone issues. A flexible multi-tasking tool like the AMK-9098 can handle tasks with multiple width narrow band EQ's but also uniquely shaped EQ slopes and curves. EQ's like the Focal Point 115HD are flexible for certain surgical processes as well, but this EQ has a unique tonal character of its own. The 9098 and 115HD can be extremely useful with very different, equally phenomenal high end sound. Where the 9098 has an aesthetic quality that is very precise and musical, the 115HD is gorgeous and rich in texture. In some circumstances, one EQ may eliminate issues easier because of the right mix of flexibility and precision, where the other may be helpful because of its ability to correct some issues while simultaneously adding some of its own rich overtone qualities into the mix. These EQ choices then become creative choices, and not just solutions for eliminating an issue.

In the case of a drumset that has been carefully tuned to work with the songs being tracked, we sometimes still run into issues despite our best efforts. Often, the initial attack of tuned Tom Toms are clear, bright, and have an attack that works great with their use, but as they sustain, the vibration of the tone becomes resonant in mid and lower Frequencies that sound like an annoying atonal hum against more important elements. This may be accentuated by the use of compression that gives the attack desired. As the toms shift from sharp, bright attack to long sustain tones that hum, and become increasingly muted, the compression continues to bring up some of the level of the extended tail, making it conflict with musical elements in the song. Individual EQ on the toms may be the most helpful way to avoid further trouble. Some may choose to gate the Toms in traditional mixing and perhaps in the DAW as well, although it is not a well-taught method in modern tracking. This can lead to further issues and may not be as effective as one would hope. In this case, a Program Equalizer, like a Pultec-Style design, or a regular "Q" width bell, can reduce the center Frequency of the hum. With 2-3 Toms, this EQ can be done on a single tom bus without reducing the positive qualities. Just a dB or two of reduction on a couple of resonant tom tones can eliminate the conflict.

I hope this gives you some ideas for digging yourself out of certain technical issues with overtones. One might say that this is a way to get 'over' the trouble with overtones!

Monday, March 3, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 8

Audio Recording Issues – Overtones That Overstay Their Welcome, Part One

Next on the list of EQ ideas is solving a rather unusual set of circumstances. Overtones are sounds that occur from various sources that are recorded in addition to the main source sound. Vocals, guitars, drums, and any instrument that is being miked live in a room can be the center of attention for this situation. Overtones can come from room reflections and ambience, from the instrument itself, and they can also come from the addition of effects at a later time, or speakers amplifying a keyboard or guitar amp. There are overtones that come from the musical response of the instrument itself. They can either work with or against the primary sound being recorded. A microphone and a preamp can add creative harmonic overtones to sound material as well. These are mostly natural responses and elements to sound ambience, resonance, vibration, string sustain, speaker cone response, and natural instrument character.

Sometimes these are beneficial and are desired elements in your recording. Other times, we might think we got a great take, but when we go to mix, we realize things are not sounding quite right. Often what happens is that an instrument resonates in a beautiful way or a room gives a great sustain, deepening a performance, or adding liveliness and power to a drum set. But, when these instruments are added together, we discover that some of the beautiful overtones are coming across as actual conflicting notes. They may complement the individual instrument performance wonderfully, but the interaction of multiple instruments recorded with their own microphones may be in conflict.

It may be that the perception that the supporting sound architecture works until it overlaps with other tracks. There is a perceived crossover of smooth, long waveforms that now conflict with others at multiple Frequencies. We don't notice the distraction until they bounce off of other sounds. We may get short bursts of shorter waves that oscillate and accentuate the fact that both conflicting waves are off pitch from each other.

In the same manner that a good chorus effect detunes an accurate pitch slightly above and below the natural pitch, overtones can conflict by forcing your brain and ear to pick up on distortion between tones that are off from each other and the original instrument. You can get very dissonant short fast waveforms from two overlapping, otherwise pleasant, overtones. Harmonics usually structure themselves intentionally and nicely above a root fundamental, but ambient overtones can clash in an endless assortment of situations.
In other instances, overtones start as a nice balance with the instrument, but as the sustain of the root note kicks in, we hear more of the overtone or room ambience and this resonance now interferes with the tonal character of another track. Sometimes this works to our advantage and other times it causes serious balance issues.

A classic example of overtone issues comes from the decision making in recording a live drumset. First, a great sounding drumset requires a knowledge of how to properly tune the drum heads. You have various pitch options, and when you make this decision, you need a balance between the top and bottom heads. Then, you need a knowledge of how to tune each drum from the next. What is the pitch difference between drums supposed to be? How many full notes or half steps sound best from the hi tom, mid tom, to floor tom? These decisions also pertain to the song being recorded. If you have an extremely tonal drumset, you don't want to spend hours tuning each head just right, only to find out that you are micro-tones off from the perfect tuning of the song, and now every sustain of that awesome drum is going to sound like a terrible pitch in the song. Anything that can be done to correct pitch before recording your tracks can offset the number of concerns come time to mix and master.

Let's pretend that you paid attention to these details. Your drums sound awesome with the songs and other instruments. The room is really grabbing this great energy from the set. Now, when you pull up the room mic's or overheads, there is a strange clash going on. What happened? Assuming there is not a phase, distance or timing issue from the multiple miking setup, you can have a variation of surface responses to pitch, reflection time, and so many variables between the attack of direct microphones and distant room microphones.

All of these issues come up in real world scenarios and must be dealt with in the best possible ways. If gobos or various room positions are available, you may get the perfect control over the room just from walking around the room and listening to takes before your final recording. If there is simply too much going on to spend all day working out the ambient kinks, then EQ may be the best response. This is especially true in the fast-paced world or recording, where every second of the session matters, and it is equally true when artists have a window of time for their best performances and creative ideas.
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Thursday, February 27, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 7


Audio Recording Issues – Actual notes that are out of balance Part 3

Sometimes, it is hard to put your finger on what you don't like in a mix. What do you do when you have a good mix, and the notes and balance all seem to be working well, but there is something about a particular instrument that still bugs you. The tone is nice, the amp is good, the reverb matches the song, the vocals are good, but something on a particular instrument just doesn't have the right feel. There is a chance that the problem isn't with any primary target notes, but rather may have something you are unhappy with in the instrument's overtones.

If the EQ balance is good and you like the instrument's tone, it is possible that it is resonating with the room or its own sustain cavity, or other characteristics, in such a way that the overtones are not a good match to the primary performance. This can mean that harmonics are being generated in the musical performance that are not flattering to the fundamental notes. Once again, you can use an EQ with a narrow band to boost and sweep through Frequencies to listen to the upper harmonics and listen for things that do not sit well with you. You can start a sweep in the upper mids and listen carefully for Frequencies that are linked to the instrument in question. You may have anything from guitar to vocal to keys before getting into the cymbals and higher Frequencies. These tones can bounce around and interfere with the energy and even rhythm of a song. Usually, with all things chosen carefully, you will be able to focus on the offending Frequencies without having to remove something that you like from other elements in the mix.

I briefly touched upon this in the last post as well, but I have a technique that often resolves certain issues if I find that removing a narrow specific issue causes something else to go off balance. By removing a very small amount of a narrow frequency, I can load a medium "Q" EQ and boost as little as 1/2 the same dB's as were cut. You can try this using the same center Frequency or slightly lower or higher, but you will hear what I am sharing if you give it a try. For example, let's say that you have an extremely powerful rhythm guitar track that sounds amazing and lively through the entire song. However, whenever it reaches a certain note, let's say in the upper mids, it overlaps with some of the character of the room's ambient sound. This room is well-tuned, and it does not have an issue with standing waves or suffer from being completely out of balance. The fact is, that location, direction, and power and other characteristics can push certain Frequencies against an ambient reflection and the perfect mic preamp and perfect mic position will capture a spike where there were no physical anomalies. People in the industry and in music science have denied this for years, but I have studied this in detail and found that there is more to do with angled walls and standing waves than what we resolve on paper.

The truth is that surface response and reflection have so much more to do with what the end result will be, than certain architectural and simplified reflective factors. So, you find yourself in a spot, because you have an amazing performance, in the perfect room, with the amp in the exact place you want with the ideal recording chain. Everything came out great, but the energy gets so strong in that upper mid register that it now has to be dealt with. You were blown away by the power when recorded and mixed, but now that the song has made it off to the Mastering Engineer, you realize for the first time that note is an issue. By slightly reducing a narrow band that catches the problem, and boosting a slightly wider "Q" at the same spot, you end up reducing an extremely small amount of data and detail in the mix, and soften the blow for surround frequencies not to lose their relationship to the complex harmonics that tell your brain that something sounds good and real and natural. What is even more interesting, is that you will be surprised just how much difference comes from the individual personality of each individual EQ. I cannot tell you how many times I have been thankful for Nebula Pro technology and my time given to translating my favorite EQ's.

You can listen to a single track and make some EQ changes and love the sound, but in a critical situation, seemingly identical band widths and shapes can sound absolutely, completely different from each other. I welcome the description of technical devices in creative terms. Some engineers despise this, and I think it is why they will always see only a very narrow and inaccurate part of the musical picture. The absolute truth is that sound has certain amazing qualities that will always exist slightly beyond our reach. Our quest in capturing the beauty of these things and analyzing the science that brings us closer to understanding sound does not offer an answer for every musical quality in the equipment we use.

I highly recommend trying certain needed surgical problem-solving processes with a few different EQ's and listen to how varied the results can be. You will love the learning process, or at the very least you will appreciate how small measures of individuality in EQ design bring you results that affect your music in ways you never would have thought of. At some point you can become an expert at predicting these variances ahead of time, and this palette of EQ's will become the artist's favorite tubes of paint!. Give these things a try before committing a track to your next mix. You will be surprised how well this can work!

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Monday, February 24, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 6

Audio Recording Issues – Actual notes that are out of balance Part 2

You can use a narrow band Equalizer to control specific notes that are out of control. This could involve increasing the volume where a specific note is too quiet, or lowering the volume if the note stands out. If the Frequency shares too many other elements of the sound in the mix with ambient sound, volume balance, other instruments, reverb, etc., then it affect which approach that works best. You may want to combine EQ with minimal band-limiting. In some cases, we can level out the balance in a mix by making very small changes in slightly wider band "Q" widths instead of honing in just on a single note. In the same situation where a low note on a bass guitar is jumping out too loud, let's assume that the kick is using this same EQ to accentuate the power of the kick's attack.

It may be possible to lower the thin narrow "Q" on this note by a very small amount, and then apply a wider "Q" eq just above, below, or centered on the same note, to revive the low end energy coming from the kick and other mix elements. This can work if the qualities in the low end are consistent with the song. But, if the rest of the low Frequencies come across mushy or too bold, this technique may not work. Another option is to slightly reduce the offending note,and use a stereo signal control. You may find that you can reduce the detail in this frequency by narrowing just the Frequency to center, mono, or simply less stereo information. This does not mean reducing the stereo signal of the entire mix, but only the note that is jumping out too much. This requires a stereo plug-in that is capable of adjusting specific Frequencies.

If it is only coming from a single instrument panned center, then this may not work. The goal is to know the combination of elements that may balance out the primary issue in mastering. By controlling the note itself and considering the balance with other instruments, using an EQ and a band-limiting compressor/limiter, you can tighten up the mix and even increase the potential volume of the mix to balance better with the volume of other songs in the same project. Narrow band EQ is a huge benefit to bringing these details into the proper context and focus.

Wednesday, February 19, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 5

Audio Recording Issues – Actual notes that are out of balance Part 1

Not everyone is aware that Equalizers can be used to affect the actual notes of an instrument, and not just the tone, hum, or noise of a track. The notes of a scale all have an equivalent Frequency range. This idea is similar to the way that radio Frequencies are transmitted. Each individual Frequency represents a sound that is a separate pitch from all other Frequencies.

With a wide "Q", meaning that the shape of the EQ starts at a center Frequency and extends a large amount below and above the given Frequency, an EQ will usually cover overlapping notes in a scale. But, with a narrow "Q", you can focus in on a single note. It is not as easy as literally manipulating each individual note on a track or an instrument in a mix. Musical notes are expressed in complex combinations, each of which is completely unique to the instrument being played. We can express a note in terms of attack, swell, sustain, decay, and many other expressions. A note with a fast attack may start with an articulated pitch and, if left to sustain, may resolve to a steady tone that is more accurate to the note played, depending on the instrument. The note itself can carry multiple overtones that are expressed as harmonics. These fluctuate with the instrument, materials, performance, and sustain and attack factors as well. The way that a note is played therefore affects how much we hear of the primary note and its harmonics, and whether there is natural fluctuation in this combination. A note from an instrument usually also carries natural ambient sound from the instrument itself, along with its environment. Even in close, direct miking, we hear things like the vibration of a wood cavity on an acoustic guitar or the hum of a string. With information coming in from anywhere a waveform can travel and bounce off of a surface, it presents a new complex abstraction of the original note.

With rooms, the note can become more scattered, with the timing spread all over the environment, and the actual sonic qualities of the room itself can stray from the primary root note. These are just a few of the factors that can affect the use of Equalizers, so you should always listen for the qualities that accompany a note and performance when making a corrective adjustment. What do you do if you have a final mix that is ready to send to the Mastering Engineer, who notices that the bass player had a couple of strings out of tune? Your song has already been mixed down and everything sounds great. But, you didn't really notice that there were a few sagging notes coming from the bass guitar. It is possible to sweep a narrow EQ and isolate the offending note, or notes.

There are many options for this scenario. Since the song is mixed, you are not likely to make a pitch adjustment that doesn't affect the other instruments in the mix, and this can be damaging to ambient sound and stereo detail to the rest of the mix as well. But, you can lessen the blow by gently reducing the volume of the offending notes. Sweep the Frequency of your narrow band EQ, place a limiter on the end of your mastering chain, and boost the EQ so that it will resonate when it hits the note being played. You can use a low quality digital Equalizer for sweeping the signal, as it is easier to hear the resonance of a bad note with a straight forward EQ, where a high end EQ will resonate better and more subtly on the same note. When I work with a situation like this in mastering, I tend to use a basic digital EQ to find the note I want to reduce, and then I will switch to my "Mastering Suite" Nebula Pro narrow band EQ to reduce the signal by a few dB.

I only make the adjustment for the duration of the note at each passage, and only when it is the most obtrusive. This technique is even more effective when used for a note that is on the correct pitch, but is simply too loud. Once again, you don't want to upset the balance of things like ambient sound and other overlapping Frequency qualities, but if a certain note stands out it may affect the volume and balance of the entire track. The question becomes whether something else is prominent in the same range. Do you have a bass guitar note that is louder than the rest of the performance, but also have a kick drum that uses the same Frequency or pitch?

You may want to EQ only at certain passages or to use less dB reduction to avoid weakening the kick drum. What about ambient sound from a well-recorded guitar or other mix elements that share this part of the lower register? You don't want to harm the mix by trying to fix a single element within it. Another option is to identify the note or Frequency and also use a multi-band limiter to slightly compress and reduce the same Frequency. This is the idea behind using Equalizers to help deal with individual notes that are out of balance.

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Sunday, February 16, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 4


Audio Recording Issues – The Right EQ for the Job Part 2

In the past, I have mentioned that the ideal mastering session ends after a second pass listening test, where the best EQ choice was not using anything at all. Despite being true, it also drives home the point that when you have a great sounding record, you don't want to get in the way if you need to make a few subtle EQ adjustments. If everything sounds solid at the mastering stage but there are just a couple of tweaks needed, then use the EQ that accomplishes the tasks without changing the personality. This is not the time for the most colorful EQ, but a musical high end mastering EQ may work well. If using something in the super-clean mastering EQ camp, you also don't want to choose something that can sometimes sound thin or clean 'in the wrong way'.

Another saying involves passing the buck; where a track needs to be re-recorded, but "we can fix it in the mix". Then, when it affects the mix, "we can fix it in the master". Then, at that stage, with the problem buried deep and poor decisions and over-corrections, we give up to say "they'll never know the difference.” The final result is the sum of all parts that come before it. A great bass track should start with a great player, instrument, strings, tuning, amp, mic, preamp, room, and choice in tracking. All things that make up the original sound should be well-defined and well-designed. The same holds true if using a keyboard, VSTi, samples, loops, etc. If the sources are chosen well, there is still a good chance you are going to use some EQ through the mix process.

There are good reasons for doing so even with great tracking and all the requirements above being met. This is where we have the creative options of the mix engineer and producer, and anyone who chooses to be involved in the creative and technical shaping of the song. Before making the signature artistic statement, try to identify things that need fixing. Whether you need a surgical EQ or a personality EQ, make sure that the tools you reach for are an extension of your own thinking. For my own work, I think of this in terms of equipment that "hears things the way that I hear them.”

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 4

Audio Recording Issues – The Right EQ for the Job Part 2

In the past, I have mentioned that the ideal mastering session ends after a second pass listening test, where the best EQ choice was not using anything at all. Despite being true, it also drives home the point that when you have a great sounding record, you don't want to get in the way if you need to make a few subtle EQ adjustments. If everything sounds solid at the mastering stage but there are just a couple of tweaks needed, then use the EQ that accomplishes the tasks without changing the personality. This is not the time for the most colorful EQ, but a musical high end mastering EQ may work well. If using something in the super-clean mastering EQ camp, you also don't want to choose something that can sometimes sound thin or clean 'in the wrong way'.

Another saying involves passing the buck; where a track needs to be re-recorded, but "we can fix it in the mix". Then, when it affects the mix, "we can fix it in the master". Then, at that stage, with the problem buried deep and poor decisions and over-corrections, we give up to say "they'll never know the difference.” The final result is the sum of all parts that come before it. A great bass track should start with a great player, instrument, strings, tuning, amp, mic, preamp, room, and choice in tracking. All things that make up the original sound should be well-defined and well-designed. The same holds true if using a keyboard, VSTi, samples, loops, etc. If the sources are chosen well, there is still a good chance you are going to use some EQ through the mix process.

There are good reasons for doing so even with great tracking and all the requirements above being met. This is where we have the creative options of the mix engineer and producer, and anyone who chooses to be involved in the creative and technical shaping of the song. Before making the signature artistic statement, try to identify things that need fixing. Whether you need a surgical EQ or a personality EQ, make sure that the tools you reach for are an extension of your own thinking. For my own work, I think of this in terms of equipment that "hears things the way that I hear them.”

Thursday, February 13, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 3

Audio Recording Issues – The Right EQ for the Job Part 1

Our goal with these 12 scenarios that require EQ starts with being able to address the “what” of the situation first. Before we can do anything, we need to know what the issue is, and then address this with the best tool. In this process, we look at the EQ as a wide range of utilitarian possibilities. The way one engineer can find a way to add sweetening to the highs and another might know how to get low's that no one else could achieve, proves the complexities of creativity and utilitarian skill.

Since this is about the use of Equalizer's strictly for making corrections as opposed to using EQ's for the sheer joy of coloration (which will surely come up!), we start by recognizing that there is something in the program material that needs adjusting. Take a few moments and let this sink in. There are times in our lives that things can have a profound effect on us, and I think this basic concept can mold an entire career.

The desire to reach for a great EQ program should be a direct response to something specific, or the capacity for doing something regretful to a track is greatly increased. When mixing a song, don't just jump to a device that is easy to use and start doing what comes naturally or what you were taught. Listen. Trust your instincts, but don't react out of habit, and don't just make EQ choices based on what someone taught you. There are times that boosting can sound better than cutting, and there are times where we get further by taking something away from an offending track than trying to boost it on another track. So, with corrective EQ, don't reach for your EQ choice before you've started listening to the things that need correcting. It is true that even incredible mixes might be 99% there, and a great mastering might involve a very picky 1%, but don't over-correct out of a need to do something or to justify your EQ arsenal.

Every tool truly has its time and place, and that doesn't have to be every session. To skim the surface with broad strokes, you want to choose the right EQ to work with each individual track as opposed to a bus group, or a bass guitar versus acoustic guitar, for mixdown versus mastering. With dozens of choices of inductor EQ's, channel strips, high voltage tube mastering EQ's, solid state op-amp EQ's, with and without transformers and more, how do we develop the instinct for the right tool for the job?

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Tuesday, February 11, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 2

Audio Recording Issues – Introduction Part Two

In every scenario we face in audio recording, mixing, and mastering, we find ourselves reaching for different tools from our audio arsenal. We have the choice of precise EQ's and musical EQ's, digital EQ's and analog EQ's, Mix, Outboard, Console, Mastering, Graphic, Parametric EQ's. It seems that the more situations that come up in the process, the more categories and modes of Equalization we can turn to.

In as many options we have available, we also find that it often pays off to use these EQ's in ways that they were not necessarily designed for. We also find that a great EQ tends to be great in many situations beyond its typical scope. Even the most flexible EQ has a personality all its own, and the most precise EQ has a personality, even in cases where we find it hard to measure where that character comes from.

Of all the tools we use when dealing specifically with Equalization, there is nothing in today's technology that can remotely come close in importance to the human ear and its interaction with the human mind. Sure, we live in the technology age, and we face the future of possibilities with every passing day. We live in a world of exponential growth in information and the development of new integrated systems of technological implementation. Some areas are good and some threaten elements of society and careers that have stood the test of time, and perhaps are best left to their own advancements.

One thing is for certain, as long as music has been created to be listened to and enjoyed by human beings, the ear will continue to be the greatest invention for the listening process. Enhancements, technology, new pioneers in future developments will come and go, and the future will bring inventions that will seem to antiquate even the greatest traditional human achievements, but even science will agree, for a time, that the most logical and direct process tends to be the most accurate. In this case, billions of people throughout our human history has had healthy pairs of ears, and although these vary in size, accuracy, sensitivity, and in the transformation from youth to later years, we see a common thread of what tends to be enjoyable to the human ear. This is not to say that the construction of the human ear lends itself to a single pathway of musical genres and constructions that are all the same, in fact the brain and one's human experience tends to give just as much feedback into the enjoyment of listening than any physical characteristics. But, we tend to notice the extreme cases under similar projections.

The majority of listeners tend to find the scratch of fingernails on a chalk board as a painful listening experience, the roar of a passing siren as painful and resonant in our brain, a passing train as noisy and disruptive. A loud clap, firework, or gunshot might make any of us leap, startled and perplexed. Likewise, regardless of preferences in music style, we might commonly find the repetition of a bubbling brook pleasant, or a beautiful chamber work from well-seasoned string players enjoyable to hear, even if it does not fall into our library of personal favorites. Our ears can tell us that something sounds good even if we don't particularly like it. For example, someone may loath the chaotic, non-traditional vocal stylings of an edgy punk rocker. The same band may have intentionally chosen a guitarist who's sonic palette is coarse and challenging on the ears. Even so, an Audio Engineer may also be able to dislike the style and be able to hear that excellent production choices have been made. The voice may not be their cup of tea, but they may be able to ascertain that the distance to the mic is a great choice, and the clarity and Frequency balance make for the proper artistic statement. That guitar may offend their musical sensibilities, but the off-axis classic recording technique may be the perfect choice for the album, and the Audio Engineer may be able to easily recognize this, despite their personal taste. This holds true for any music style and any devoted professional, or aspiring, pair of ears. This is the wonderful interaction between the natural human listening apparatus and the brain that has been designed to make use of them.

Between the mind and the ears, we have technical messages sent and received, but also we have personality, learning, concentration, focus, and decision making that can become so complex, it is a wonder of remarkable ingenuity in itself. Why am I going on about the human ear and the human mind? This seems to be the perfect place to mention such a thing. We are entering into a deep analysis of 12 scenarios that come up in the tracking, mixing, and mastering process. The greatest tools in the world will fail us, as human beings, if we do not use them in their best context, and especially if we allow these tools to rule over us instead of the vice versa.

The human ear has a remarkable ability to recognize extremely small variations in volume and harmonics. The way that electronic gain-staging affects the analog qualities of an EQ are additive and combine with the "Q" width, the actual shape of the EQ, and the amount of boost or cut. The energy of the EQ fluctuates depending on the material being fed and every setting. We find that having several primary tools allows us to choose a specific character that matches the instrument, mix, or bus group. EQ's that use transformers tend to have an added dimension of weightiness to the sound. While they help to balance and float the signal and to keep things clean and low in noise, they also add a certain thickness and tone from subtle to recognizable. With heavier inputs, the transformer can be driven into intentional harmonics.

These play a role in affecting the personality of the EQ filters. Low Frequencies carry a long waveform and can be a larger challenge to keep absolutely clean without pushing the amplification ceiling into slight distortion. When combined with transformers, this can gently compress signals while also adjusting their frequency, giving a wide sonic palette to work from even with a single device. The Op-Amp, Tube, Transistor; they all play a role in treating the sound in a unique colorful way, where transformerless devices have the potential to react in a more transparent manner, they can lead to more audible artifacts in the EQ filters themselves, where caps and transistors interact with specific Frequencies as well. All of these factors work together to affect the analog nature of sound, and this is what we are working with when providing you with a new EQ product, whether for Nebula Pro or as a stand-alone audio plug-in. These are all factors to remember when choosing the eq that is right for the specific task at hand. Remember that these elements have an affect on the signal just as the shape and type of EQ also have an affect. Whether you need a surgical EQ or a personality EQ, you want to have at least a couple of favorite "go-to" options that shape the sound the way you want to hear it. For my own work, I think of this in terms of equipment that "hears things the way that I hear them.”

Monday, February 10, 2014

How To EQ – Mixing and Mastering - CDSoundMaster.com – 12 EQ Issues Part 1

Audio Recording Issues – Introduction Part One

The topic for this series of Posts is about specific audio recording issues that commonly come up in the tracking, mixing, and mastering processes. The Audio Engineer often plays a combination of these roles in the chain, or may specialize in a niche position.

I have addressed an outline of 5 specific types of Equalizers and how they are used in daily tracking, mixing, and mastering. I followed this with covering 10 common EQ modes that we work with under these 5 categories of EQ designs, both in analog and in digital domains.

Now, I would like to break this down into a process of analyzing 12 specific scenarios that we face, with a groundwork provided of EQ types and EQ modes. What situations arise that call for us to be the EQ Artisan, making creative decisions, and when do we run into EQ emergencies that call for an EQ surgeon? Although the situations are ongoing and extremely expansive, I have outlined 12 specific scenarios that I think are interesting to discuss at length. I began this topic throughout my 2013 Blogging year, but as many of you know, it has been an incredibly eventful year for audio recording, including releases and updates that CDSoundMaster has taken part in with Acustica Audio, like the Cooltec EQP-1 Audio Plug-In that we are so proud of, and our independent Nebula Pro libraries that we believe are among the world's finest audio processing options available today. Needless to say, my Blogging has been unsteady, and has shifted topics many times throughout the year as a result.

So, I am going to begin this topic fresh, uninterrupted, and I hope that it serves as an informative tool for you. As I have stated in the past, we use tools in order to leave a creative mark on our work. We define our artistic decisions with the hope that they provide a signature, whether it is a strong artistic statement or the decision to always remain true to the song or music style. Productions are approached in so many different ways, and every choice can have a profound effect on tracking, mixing, and mastering.

Regardless of your approach, you want to be sure to identify key factors in making improvements to your mix. The following is list of scenarios that call for important EQ decision making in tracking, mixes and mastering:

1. Actual notes that are out of balance.

2. Overtones that overstay their welcome

3. It sounds great on its own, but...

4. Nice sound when tracking, but way too much "-----" when blending parts together

5. Multiple mic's setup to track the same instrument and need the right balancing together

6. Two birds, one stone

7. Separation or glue

8. Overlap in the mix causing unwanted frequency bumps

9. Compressing and limiting changed something that needs to be fixed

10. What happened to my stereo field?

11. Comb what?

12. Making it stand out or bringing it all together

These processes come up all the time in music production. Every Audio Engineer has their own approach to address these situations. There are also Producers, Engineers, and others involved in the recording industry that have not run into these issues, or have not been equipped to handle them. Addressing these situations can show the myriad of scenarios to help prepare those that have never run into them, are lost as to how to handle them, and also those that are well-trained, but may be looking to broaden their experience and offer more ways of approaching the same situations. This is also about showing how the mastering process can lend information to the Mixing Engineer, providing ideas about how to better prepare recording sessions for a successful outcome.

Thursday, February 6, 2014

How to EQ – 10 Equalizer Modes – Part Eleven - CDSoundMaster.com

Audio Recording with Equalizers – 10 Equalizer Modes – Part Eleven – Graphic or Parametric EQ

The final Equalization modes that I would like to discuss are Graphic and Parametric EQ's. These are two different modes, but since they are the two primary choices of EQ design that the user will choose between, I wish to close in a combined discussion on these modes. There are other EQ's, like Paragraphic among others, but Graphic EQ and Parametric EQ are the two predominant operation modes. You can technically design an analog Graphic EQ and Parametric EQ using the same basic signal path, and therefore with the same sonic integrity and character. However, they provide a noticeably different range of possibilities.

The Graphic EQ is defined by having multiple fixed Frequencies, each with their individual Gain, all available at the same time. We see these everywhere from live sound installations to car stereos and home stereos. Because the Graphic EQ is used so commonly in many scenarios outside of the studio, some people make the mistake of thinking that it is not meant to be used in the studio at all. In some ways, we truly tend to under-use the Graphic EQ. It is largely because the Parametric EQ was such a radical invention at the time it was developed, that it become the norm in most EQ designs. For the Console EQ, Parametric makes perfect sense, because the user can be provided a lot of flexibility in a small linear space, where a Graphic EQ on every channel would take a lot more space. For Outboard Equalizers, we often see the Graphic EQ being used to control the balance of the outputs in a given room, to EQ the speakers themselves, or for monitoring in multiple scenarios. Many live mix Consoles will have a Graphic EQ on the main output, which perpetuates the belief that Graphic EQ is not used in typical tracking, mixing, or mastering.

The reality is that the best sounding Graphic EQ's can be an incredible mixing tool, and although they are almost never used as such, they can be incredible for Mastering as well. In general the Graphic EQ tends to provide each EQ Band at the same precise width, with one Band backed up to the next. Since each band controls its own independent EQ with the same amount of boost and cut Gain, you can sculpt the entire output spectrum with individual control. With a Parametric EQ, you have various individual modes that help shape the output and the Band EQ's can be used in a flexible manner that we will not find in a Graphic EQ, but in the case of the Graphic EQ, we can add and subtract exactly the amount that we wish to for each part of the Spectrum needed. This can work wonders on individual tracks and on the main outputs. The Parametric EQ was originally designed for hand-built mixing consoles that became the world famous GML and Sontec lines of mix and master EQ's.

The Parametric design is believed to originate with these developers. The Parametric EQ was the first design that allowed the user to tune in on the exact Frequency desired, adjust the “Q”, and even select multiple bands for specific tasks, some of which could even overlap other bands. Since the Frequency, width, and Gain are all adjustable, the user can fine tune their EQ needs with a great measure of flexibility. Because we have become so accustomed to having the Parametric design for many years, it is hard to imagine not having this flexibility available to us. In analog form, the Parametric EQ provides us the structure, and the construction of the individual brand of EQ provides the individualized sound character.

Inside the computer, we are presented an increase in visualization options for the Parametric Equalizer, showing the movement of Frequencies, the width options, and allowing us to grab, bend, and stretch positions while seeing the shape on the screen. The Graphic EQ tends to exist in the digital realm as an emulation of the analog device, usually only adding the flexibility of input and output levels and volume visualization. I highly recommend exploring the EQ options in different formats, and always let your ear lead the way. Functionality is crucial, but sound quality is always the ultimate aim.

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Tuesday, February 4, 2014

How to Mix and Master with EQ – 10 Equalizer Modes – Part Ten - CDSoundMaster.com

Audio Recording with Equalizers – 10 Equalizer Modes – Part Ten – Shelf EQ

The Shelf EQ is a vital tool in the art of recording, mixing, and mastering music. It is called a Shelf EQ because it does not taper off at the ends, but remains constant like a shelf until the end of the spectrum. If you use a high Shelf EQ that begins at 10kHz, it will continue in a curve until it reaches a certain point and then remains at that level as far as the upper Frequencies continue. If you are working at a sample rate of 44.1kHz, then the high shelf EQ will continue all the way to 22,050Hz, and a low Shelf EQ will continue all the way to a theoretical 0Hz.

In actuality, it takes roughly 10Hz to reach the edge of a digital wave file, and approximately +/-10dB, but this is practically irrelevant to any audible recording. The Shelf EQ will sound and mostly appear perfectly straight beyond its edge, curve, or slope. A Shelf EQ will normally have Fixed Frequency positions to choose from along with +/- Gain options. As an example, you may have a Program Equalizer with 30Hz, 50Hz, and 100Hz Shelf EQ positions with boost and cut Gain, and you may have high Shelf with 6kHz, 8kHz, 10kHz, 12kHz along with boost and cut Gain. All of these options will extend all the way to the extreme high or low spectrum beyond the starting curve or slope, but the Frequency that is designated will mark the position that the EQ goes from flat to adjusted. In some ways, you could look at a Shelf EQ as being a Bell-Shaped EQ where only one side of the EQ has the Bell, and the other side continues at the height of the Bell. Shelf EQ is not always the exact same slope or curve.

There are some rare cases where a “Q” control that would be used in Band mode, doubles as an adjustable edge for the Shelf EQ as well. In this case, the user is able to not only select the Frequency from which the Shelf will begin processing, but also the shape of the edge Frequency that makes the transition from flat to Shelf. In this case, the user can decide whether the transition is extremely gradual or a quick, sharp transition.

Monday, February 3, 2014

How to Mix and Master with EQ – 10 Equalizer Modes – Part Nine - CDSoundMaster.com


Audio Recording with Equalizers – 10 Equalizer Modes – Part Nine – Band or Bell-Shaped EQ

The Band or Bell-Shaped EQ is one of the most important and common EQ modes available today. The Band mode denotes a single location on the EQ spectrum. It begins and ends at the intersection of 0dB Gain. The width of the Band EQ is determined by the “Q” width setting. The Band EQ runs at a distance from its first point, which is the lowest Frequency of the Band, to the second point, the highest Frequency of the Band. When adjusting the Band EQ Gain, it selects the very center point of the Band In most cases. The typical Band EQ is symmetrical, so its central point is selected from minimum to maximum boost and cut Gain points. Typically, Gain can be selected from +/-10dB, but we often see as much as +/-12dB and even +/-16-20dB. The wider the range of Gain, the more potential there is for variability in its response. Sharp “Q” width slopes tend to be steeper and more resonant than smooth narrow shapes and much more than wide “Q” width.

Most Band EQ options are called Bell-Shape EQ. As you might guess, this is named for the height and smooth shape at the peak Gain of the Band EQ. This is usually the most visually consistent at moderate “Q” settings. The more narrow the “Q” setting, the sharper the tip will become. Some Band EQ's are sharper in narrow “Q” and some tend to maintain the same Band shape. Most Band EQ's have a lower range of Gain at their wider settings. The Bell-Shape will be extremely gradual and smooth and the peak levels may be as little as half the amount when they are at the narrowest setting.
It is possible, depending on the intention of design, that the Band EQ is not symmetrical when comparing boost Gain and cut Gain. Some Band EQ's are designed to be a perfect mirror image at positive and negative Gain settings. If these EQ's are plotted on a graph so that you can see all settings and Gain at once, it will look like a perfectly symmetrical oval shape. Other Band EQ's are designed to have a rounder, wider, smoother Bell-Shape when given boost Gain and a sharper, narrower, deeper cut Gain. This is seen as making smooth additive changes that are sonically pleasing and making cuts that are more corrective and affect less of the surrounding Frequencies.

Some Band EQ's are not symmetrical from the edges to the peak or central point. These are rare in comparison, but they can give the user a very unusual and unique creative control that otherwise does not exist. These EQ's tend to have a regular initial distance from point to point, but as Gain is increased beyond a few decibels, there is a curve to the center point, much like a hook or claw. This allows the ability to gently boost or cut a center point and then reduce more from the Frequency just above center. As the point sharpens above the center, there is the increasing ability to cut a very narrow amount of corrective EQ.

When using Band EQ's, I recommend testing out various settings. If the Frequencies are fixed, get to know what it sounds like at boost and cut, and at the steepest settings, to learn if it becomes more subtle and narrow as the Gain is increased or if it remains fairly curved and more audible. If your Band EQ is adjustable in “Q” width, test it out on different material to get used to its affect at different widths. There is always more to the affect of an EQ than the visualization of its shape, so listening is the key to becoming familiar with its individual personality. You will find that you lean more towards some settings over others, and this will help you to develop your personal mixing or mastering style.
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Wednesday, January 29, 2014

How to Mix and Master with EQ – 10 Equalizer Modes – Part Eight - CDSoundMaster.com

Audio Recording with Equalizers – 10 Equalizer Modes – Part Eight – High Cut and Low Cut EQ

In my last Post I mentioned that some beginners get confused by terminology when they come across settings like high and low pass filters and EQ's. It is logical, since it is a strange naming of things, but once we understand that pass quite literally means letting a range of the spectrum pass through, we can start to see the reason for using these settings. So, why would there be a different EQ mode for high and low Cut EQ's? Well, technically we could get by with just using one or the other, since they are often synonymous with each other. A high cut EQ can work essentially the same as a low pass EQ and the same with a low cut and a high pass. A high cut EQ will remove the audio signal above the target setting, and a low cut EQ will remove the audio below the target setting. One could argue that this seems more logical than a “pass” EQ. Not everyone may catch on to the logic of a pass filter as soon as the obvious terminology of a cut EQ. But, does this mean that they are essentially the same thing, and if so, why would they be called one instead of the other? The truth is that one EQ mode can “pass” for another (pun definitely intended). Cutting lows below a certain point is the same as allowing all audio above that point to pass. But, the factors that surround pass and cut filters can be different. Typically, a pass filter is a preset shape, and only the pass Frequency may be changed. With a cut EQ, it is possible that the same Frequencies and even same EQ shapes may be chosen as the pass filter. But, sometimes with cut, we may have a different array of frequencies and we may also have the ability to adjust the Gain, depending on the EQ.

The methodology of the cut Frequency can vary, from the amount of decibels per octave that are cut to the type of filtering process used to achieve the goal. As we will see when looking at Shelf EQ's, the selected Frequency is not the only factor determining a pass or cut filter. The shape of the filter tends to serve a reason that some designs call the setting a cut or pass filter.

Although it is true that it can designate the same thing, there is more variation involved in the potential settings of a cut EQ slope and shape, depth, and options for Gain control. Cut EQ can designate that it is offering the user the opportunity to eliminate a Shelf-type reduction of a wide range of Frequencies above or below the threshold, but it also leaves the options open to define how deep the cut is, and whether it is a soft taper or a strong brickwall cut-off. With a pass EQ, the only factor that the user is to consider is the Frequency that serves a cut-off point, and everything beyond that threshold is to be completely gone as best served by the design. So, in its purest form, the cut and pass filters are very similar, but cut tends to share characteristics with the Shelf EQ and pass EQ, where there is some room for flexibility in shape, Gain, slope, and depth, but the bottom line is the goal to cut Frequencies to a deep setting, with an understanding that some designs allow for more flexibility, and still others may have a set cut-off filter and a separate Shelf option.

How to Mix and Master with EQ – 10 Equalizer Modes – Part Eight - CDSoundMaster.com

Audio Recording with Equalizers – 10 Equalizer Modes – Part Eight – High Cut and Low Cut EQ

In my last Post I mentioned that some beginners get confused by terminology when they come across settings like high and low pass filters and EQ's. It is logical, since it is a strange naming of things, but once we understand that pass quite literally means letting a range of the spectrum pass through, we can start to see the reason for using these settings. So, why would there be a different EQ mode for high and low Cut EQ's? Well, technically we could get by with just using one or the other, since they are often synonymous with each other. A high cut EQ can work essentially the same as a low pass EQ and the same with a low cut and a high pass. A high cut EQ will remove the audio signal above the target setting, and a low cut EQ will remove the audio below the target setting. One could argue that this seems more logical than a “pass” EQ. Not everyone may catch on to the logic of a pass filter as soon as the obvious terminology of a cut EQ. But, does this mean that they are essentially the same thing, and if so, why would they be called one instead of the other?
The truth is that one EQ mode can “pass” for another (pun definitely intended). Cutting lows below a certain point is the same as allowing all audio above that point to pass. But, the factors that surround pass and cut filters can be different. Typically, a pass filter is a preset shape, and only the pass Frequency may be changed. With a cut EQ, it is possible that the same Frequencies and even same EQ shapes may be chosen as the pass filter. But, sometimes with cut, we may have a different array of frequencies and we may also have the ability to adjust the Gain, depending on the EQ.

The methodology of the cut Frequency can vary, from the amount of decibels per octave that are cut to the type of filtering process used to achieve the goal. As we will see when looking at Shelf EQ's, the selected Frequency is not the only factor determining a pass or cut filter. The shape of the filter tends to serve a reason that some designs call the setting a cut or pass filter. Although it is true that it can designate the same thing, there is more variation involved in the potential settings of a cut EQ slope and shape, depth, and options for Gain control. Cut EQ can designate that it is offering the user the opportunity to eliminate a Shelf-type reduction of a wide range of Frequencies above or below the threshold, but it also leaves the options open to define how deep the cut is, and whether it is a soft taper or a strong brickwall cut-off. With a pass EQ, the only factor that the user is to consider is the Frequency that serves a cut-off point, and everything beyond that threshold is to be completely gone as best served by the design. So, in its purest form, the cut and pass filters are very similar, but cut tends to share characteristics with the Shelf EQ and pass EQ, where there is some room for flexibility in shape, Gain, slope, and depth, but the bottom line is the goal to cut Frequencies to a deep setting, with an understanding that some designs allow for more flexibility, and still others may have a set cut-off filter and a separate Shelf option.

Tuesday, January 28, 2014

How to Mix and Master with EQ – 10 Equalizer Modes – Part Seven - CDSoundMaster.com

Audio Recording with Equalizers – 10 Equalizer Modes – Part Seven – High Pass and Low Pass EQ

Many people start recording their own music and learning the basics in mixing because they have an idea for a song, and others get involved because they have played an instrument for some time and want to record themselves in the context of a song with other instruments. Still others join a band, and once they sound decent they want to document their efforts, and some like to sing and write lyrics and try their hand at making their own tunes, either with MIDI or samples. Whatever road that gets them there, if we are talking about the self-taught beginning recordist, one thing that typically mystifies the early learner is the high pass/low pass filter or Equalizer.

They might have an easy grasp on what an Equalizer is, and what makes for different Frequencies, Spectrum, Gain, among other vocabulary. But, high and low pass may not automatically make sense. Especially if they learn about “pass” at the same time as they learn about “cut” they may be even more thrown for an answer.
The truly simple explanation for high and low pass EQ is to take it for face value. A high pass Equalizer allows everything above a certain Frequency to “pass,” meaning that all of the signal above that setting will remain and will not be removed. For example, a high pass EQ set to 100Hz means that everything from 101Hz and up will remain. This also means that everything below 100Hz will be removed.

The same concept applies to low pass EQ. In this case, the low signal spectrum is going to be allowed to pass. So, in the same situation, if a low pass EQ was set to 100Hz, we would no longer see any audio above 101Hz, thus we would only hear low Frequencies.

The “pass” EQ is designed to isolate only what is needed and to remove everything that is causing trouble at a fixed point. Because it can make a very strong statement and a very obvious change to the signal, the “pass” point is usually not set, but is usually given several fixed Frequency options. These are usually chosen at points that are known to have typical audio issues. One point might be set to remove low end rumble, and another may be set to reduce grounding noise or audio interference hum. Another setting may be set below our usual hearing level just to clear any noise that is not intended just in case it is there. Higher Frequency high pass filters, like those above 80Hz, sometimes as high as 150Hz or even 200Hz help to clarify a signal that does not rely heavily on low Frequency content. This could be anything from a mid-to-upper piano part or vocal, a guitar or cymbal, and numerous other items. A pass filter can be used on an effect channel like reverb or time-based effects like delay or chorus or flange, to separate out residual effects from their original signal, making the dimension of a song more intricate.

The low pass EQ can be used to get rid of buzz or hum sitting on top of a clean bass guitar line, or change a slap and tap string artifact to sound more like a purposeful tonal performance. High pass can be used to remove all upper Frequencies and hiss and noise that is recorded as part of a low Frequency signal that is not desired. It could also be used on effect tracks to change the way an effect sounds on content that otherwise has a lot of high Frequencies, but it can also be used at the highest Frequency option supplied on a low pass filter to create a special effect from a track that normally has more spectrum in the sound, like making a voice sound like it is coming from a telephone or an older recording device.

It is very rare that a pass EQ will be completely variable, meaning that it is usually provided with a few fixed Frequency options that make for a usable utility for removing trouble above or below a certain point, but this is usually not given complete flexibility. It is also not as common for there to be only a single fixed pass Frequency, since there can be different spectral issues that come up on a regular enough basis that call for using pass filtering options.