Compressing Vocals PART 1 (Sandpaper Theory)

The other 3 parts in this compression series:

PART 2: Compressing Vocals Part 2 (Ducking)
PART 3: Compressing Vocals PART 3 (Limiting)
PART 4: Compressing Vocals PART 4 (Parallel Compression)

When I think about when I should use compression there’s four ways that come to mind.  Now at the time of this posting these are my go to compression techniques, however, as I continue to grow, it could change.  In this post I am going to talk about the theory of using compression like a piece of Sand Paper.

The Sandpaper Theory

Just imagine a woodworker.  He just finished cutting up all his pieces to make a chair.  Now he could just put them all together and he would have a decent enough chair.  But it would be much better if he took some sand paper and smoothed down the pieces to create a softer more attractive surface.   That’s sort of how I look at compression when applying this particular technique.  I’m using the compressor not to force my will onto the sound but to actually have the track interact with the compressor so it actually sounds better.  Im trying to smooth out those harsh edges that make the vocal slightly unpleasant to listen to.  With this technique a little bit really does go a long way.  Im trying to make the compressor do as little to the sound as impossible so I can stay true to the original sound.  It’s all about preserving those dynamics and in this case, just shaping them to something better.

Putting it Into Practice


With this specific technique, I’m normally looking to shave off an average of about 1-3db, sometimes more but usually not.  I like a pretty fast attack around 2-10ms because I want enough of the initial transient to come through with out being effected.  This will help ensure that my vocal stays sharp and commands the front of the stage.  If you use too fast of an attack it will shave off too much of the transient resulting in a sound that becomes a bit “cloudy”.  however it has happened when the sound was actually too sharp that an attack of almost 0 was necessary to help smooth it out.


I would tend to use a medium to long release in this situation because I want the compressor to shape most, if not all, of the body of the sound.  Imagine you have a piece of wood that was 2 feet long and you needed most of that wood sanded down to smooth it out, would you just use the sand paper on the first 2 inches?  No you wouldn’t, and that’s why I tend to use a longer release so it can shave most of those peaks.  Remember we are barely taking anything off to begin with but once the compressor does engage we want most of that sound to be shaped.  Unfortunately I cant give specific release times because it honestly changes all the time.  A good way to try and find that perfect area for release is to set your attack to about 2-10ms (temporarily, we can change it after) and set the release to the fastest possible.  Now pull your threshold down until it compresses more than normal (5-10dB).  Then take the release portion of the compressor and start increasing the value, making it slower.  You should be able to find an area where the compressor works with vocal in terms of timing.  Now disengage the threshold and start slowly bringing the threshold back down until the compressor starts shaping the sound.  Try not to take it too far where it rids the sound of its dynamics, we just want a smoother vocal that’s easier to find and listen to.


I know some engineers prefer to use a smaller ratio and compress a little bit harder.  I prefer to use a higher ratio and compress less.  I guess I prefer the sound more.  That being said, every situation tends to be different but I usually go for a ratio of about 4 – 8.  I want a higher ratio because when the compressor engages I want it to act aggressively.  Even though most of the sound isn’t crossing the threshold, anything that does cross that threshold I want to be pulled back a lot.  Again I’m only taking out 1-3 dB at a time so if this technique is done properly the dynamics should sound better and not worse.


This is the part of the compressor that you would have to think about the least because once the Attack, Release and Ratio have been figured out, you can just adjust the ratio until you like the sound.

YouTube Video Source: How to Compress Vocals (Sand Paper Theory) [1/4]