Music Articles From

Back to articles index | Home |

How To Use Comperssors? and is there one setting that works for all?- bt John Vestman
Compression Q&A

>I record with Cakewalk... I have experimented with many different compressor and EQ settings and still can't get a professional sound. I don't think I fully understand compressor and EQ settings. Can you help me with settings? -Shannon

Compression and limiting is simple, and highly under-explained. All it is... is an automatic volume knob that turns down the signal a certain amount, based on the settings. Generally the effect is that when the loud spots are turned down, the overall level can be brought up and the less-loud areas of music become easier to hear.

The first setting is the *threshold* which is the point at which the device works. Kinda like the threshold of a doorway is the point at which you step into the other room - it's a line you cross over. So before the threshold is reached, nothing happens to the signal. *After* the threshold (after you step over the line), the device starts turning the volume down.

How much it's turned down is determined by the compression ratio. 4:1 compression ratio means that for every four dB of signal that goes into the unit, it turns it down so that only 1 dB comes out. 8:1 means that for every 8 dB that's put in, an increase of 1 dB is what goes out. Often we see a meter reading called "Gain Reduction" which is how much the device is turning the signal down (that's what I prefer to look at on the meters).

The attack time is when (how soon or how fast) the gain reduction unit starts altering the sound. The release time is when (or how long until) the unit stops altering the sound. The slower the attack time, the more the initial signal gets through the unit without being altered. Slower attack times let through more peak (and the immediately trailing) material because it waits longer to start working.

Limiting (which is really just more compression) starts up at 10:1 and goes up from there. Since limiting is really turning down the signal a lot at once, it's faster and mainly used on peaks which are occasional, not constant. Used properly, limiting should be hardly detectable because it's controlling shorter amounts of sound.

Since 2:1 - 6:1 is a more subtle amount of alteration to the sound, it can be used for more containment, for instance on vocals, bass, etc. Stereo mixes, however, don't sound good contained. In mastering, I'm very careful about keeping the openness to the sound of a mix, so I highly recommend not compressing the stereo output of your console. If your meters are swinging too far "into the red" check on individual voices and instruments that need the containment.

Frankly, I'd leave off the limiting in mixdown too. If you put too much compression or limiting on your mix, there's nothing I can do to remove it if there's too much of it. Most of the time, I use limiting and compression in different ways on different songs, so I prefer to have a wider range of options to pick from.

The other reason that I don't recommend compressing the stereo mix is because it sounds too good. Same thing with a Finalizer in mixdown. Since it sounds so good, it tends to make you not work as hard at getting the mix to be totally exciting and punchy as you want it. Working hard on the mix (within reason) adds a level of excitement to the song. It adds a "performance" element, if you will, to the mix process. When you put more energy into the mix, it somehow comes out more on the cd.

I had great fun mixing through a Finalizer several times, thinking how good it sounded, until I got these mixes in to the mastering room. Right before my ears, what I thought was exciting and vibrant was more soggy *within* the mix. The highs and lows were good, but it wasn't up to the song's potential. Once again, I was reminded that another gadget often does *not* take the place of solid basic music-based engineering.

Even riding faders is a very correct form of gain control, and with your ears as the guide, it's a very musical form too.

>What type of EQ & comp. for vocals, guitars, bass and drums?

There just isn't a formula, because every musical element is unique and deserves the listening treatment. Eq'ing is a another article in itself. For now, as far as compression, I like 4:1 for vocals and bass, maybe 5:1 for guitars, and generally I don't compress drums unless I'm going for an effect, or it's just needed in the mix. (I do like gating toms slightly.) If the drummer isn't consistent with the volume of his/her playing, I attempt to iron that out at the tracking session, not the mixdown. Sampling and replacing drum notes is an option, but ultimately, it's more of a win for everybody if the player (the source) is held to a higher standard.

As far as getting a professional sound, there is just a learning curve, and every engineer goes through it. I can remember hearing records thinking, "The high end sounds so darn much better than what I'm doing!" Then I'd work and work on the high end, and think, "That record has much better bottom than mine does!" Then I'd work and work on the low end, and then I'd think, "Why can't I get the mids to sound like that record?" And the list goes on. Striving for warmth, clarity, smoothness, width, apparent loudness, mono compatibility, etc... it's just a process. Experience is the only teacher that is one-on-one with you at every moment of your career, and the frustration that goes with it is a valuable component of this process, because it motivates you to *ask* the questions and seek the answers.

Guideline: Generally, one answer comes up again and again. "Less is more." Tweak as much as you can at the source, then progressively less as you go up the next layer up the chain, and so forth. Therefore, doing nothing at the stereo mix buss is right in line with this idea. And...remember Rule #1 - there are no rules. Be as unique as you want to be - don't rivet yourself into any one idea if another one will work better. Sometimes mistakes even lead to cooler ideas. We all experience the mistakes and frustration, so don't be hard on yourself at these times. Just acknowledge your feelings, let them go, and enjoy the ride along the way.

John Vestman is a veteran mastering engineer with over 26 years in the industry. His credits include: Hole (Courtney Love), Juice Newton, Ambrosia, Andre Crouch, The Wynans, Great White, Candyman, Billy Davis Jr./Marilyn McCoo and more. John Vestman Mastering is located in Orange County, California, and his web site offers over 40 pages of information about successful studio recording techniques and sound philosophy.

Back to articles index

Copyright © 2001 Galaris LLC. All rights reserved.