By: John Mills

I want to give you some basic settings to get you started on specific instruments and situations, I also want to dispel a nasty myth that many people, who don't understand compressors, typically believe.

First let's hit some of those basics. Here are a few thoughts before I give you the magic numbers.

• When learning compression, try starting out with the �auto� button engaged. If your compressor has one, this button automatically sets the attack and release for you. It is not always correct, but it does do a pretty good job of guessing what you want to achieve.
• If you have an OverEasy button, turn that on too. OverEasy is a trademarked process of controlling the compressor's knee and was developed by dbx, but simply put, it is a little more musical sounding type of compression.
• When you feel like you understand the threshold, ratio, and output sections then go after learning the attack and release knobs.
• One other thing to note is that every brand of compressor sounds a little different. That's why top studios have many different types of compressors. For our practices though, we aren't interested in the subtle differences, but more in controlling the dynamics of our instruments and vocalists.
• �I need more compressors� is not always the solution. I run a Yamaha DM2000 digital soundboard all the time. It has 96 compressors installed. You'd think that I could just put one on every channel, but honestly I still only use about 6 or 8, depending on what the band is doing.

What should I compress?

I typically compress vocals, drums, bass, and acoustic guitar. When I'm short on compressors I make decisions in that order. If I really need a compressor on the snare, but I've used 3 on vocals, I might consider putting the 2 background vocals through a subgroup and compressing them together. That would free up one compressor for the snare drum, but then the louder of the two vocalists will be triggering the compressor, so that's not always desirable. When possible, it's easier to have one compressor on one channel.

Vocals:
The idea with vocal compression is to smooth out their dynamic range so they will sit in the mix better. When Sally goes for that high note in the Sandi Patty song, it shouldn't make your ears bleed. As well as when she goes to a quiet section we should still be able to hear her.
Threshold: Set so there is always a little compression taking place. Maybe �1db on soft sections and �10db on loud sections.
Ratio: 2:1 for lead vocals, and 3 or 4:1 for background vocals.
Attack: Set as fast as possible.
Release: Should be around 40ms.
Output: Don't forget to bring the output back up about the same amount as how much gain reduction is showing on the meter. If you are seeing �4db on the gain reduction meter boost the output by +4db. That way you make up the gain you lost in the compressor.

Drums:
The biggest benefit of compressing drums aside from controlling their dynamics, is that we can achieve a punchier sound. Try these settings. One compressor on a submix of the drums will often be a good solution. Though, I prefer to have an individual compressor on each drum.
Threshold: Set so there is about �6db on normal hits. More compression will return a more �squashed� sound, which is often desired, on a snare.
Ratio: 4:1
Attack: 50ms to 70ms. Making the attack longer will give you more stick sound. Making it shorter will give you more pop.
Release: Set around 300ms.
Output: Don't forget to bring the output back up as detailed under the vocal settings.

Bass:
Since the bass guitar is the feeling, and driving force behind most modern music, I tend to want it pretty solid. I don't like the low frequencies jumping around as if they were coming and going.
Threshold: Set so there is about �6db on the gain reduction meter.
Ratio: 4:1
Attack: 45ms
Release: 200ms
Output: Don't forget to bring the output back up as detailed under the vocal settings.

Acoustic guitar:
I like the acoustic to have a nice attack but also to be consistent. Going from finger picking to hard strumming will require a bit of a threshold adjustment usually, but these settings should get you started.
Threshold: Set so there is about �3bd on the gain reduction meter.
Ratio: 3.5 :1
Attack: 160ms
Release: 400ms. Give or take depending on how fast the song is. You should see the meter fall just a hair faster than the natural decay of the note.
Output: Don't forget to bring the output back up as detailed under the vocal settings.

Strings or general orchestra sectional mics:
I like to hear the string section. If I have extra compressors available, try these settings to get a little more out of the mics over these sections. Be careful though, having a mic covering an area, usually means it is a little far from the instruments. When compressing that mic, it tends be more sensitive. Watch out for feedback as well as picking up too much of other surrounding instruments, or noise sources.
Threshold: Set so there is about �1db on the quietest sections
Ratio: 2.7:1
Attack: Set relatively fast, around 2ms.
Release: Set somewhere around 450ms and 550ms.
Output: Don't forget to bring the output back up as detailed under the vocal settings.

Remember, these settings are only guidelines. If it sounds bad, don't blame me, trust your ear.

Oh, and that nasty myth I mentioned at the beginning, compressors don't fix bad technique. Instead of slapping a 5:1 compressor on that vocalist, because she can't seem to hold the mic in the same place, why not spend some time going over proper mic technique with her. Be nice. A humble sound person who teaches, and is also teachable, is the best kind to be.