#gainreduction

WHAT IS A COMPRESSOR?

Compression is the procedure that is used to compress the audio signal in order to reduce the louder parts of a signal and “match” them with the softer parts and achieve a more “constant” volume throughout the whole signal source.

Threshold – How loud the signal should be in order for the compressor to start working. If the volume doesn’t touch or surpass the Threshold then we will have no compression at all.

Ratio – How much compression we use. For example, if the Compression Ratio is set at 6:1, then from the 60db that surpass the Threshold we keep only the 10db. If we set the ratio at 2:1 we’ll only keep 10db out of the 20db that will surpass the threshold and so on…

Attack – How fast – in milliseconds – the compressor “catches the signal” that surpasses the Threshold. 30ms Attack means that it will wait 30 Milliseconds and then it will “catch” the signal and start compressing it.

Release – How fast – in milliseconds – the compressor will release the signal after it compresses it and drop it back out of the Threshold. Most of the times the Auto function works properly.

Knee – It’s similar to Attack but not so important that’s why you may not see it on every compressor. Hard Knee means that our compressor will catch the signal aggressively and Soft Knee means that the compressor will catch it smoother and the further-er it surpasses the Threshold.

Make-Up Gain – When we use compression we reduce the signal so we need to get it back to where it was. If we compress 2db then we need to add 2db back.

Gain Reduction (GR) – This is how much db we reduce – Our main aim. Most of the times I find myself using up to -6db. Use more of this and the audio will sound “squashed” and definitely edited and we don’t want the listener to think “something weird is going on here”. If the listener that has no knowledge about recording and music production thinks that something is going on then we definitely didn’t do a good job.

Output – You can increase or reduce the final volume. But since the compressor’s job is not to increase the overall volume.

HOW TO USE A COMPRESSORS.

1. No matter if you use an analog compressor or a VST compressor the setup is almost the same. Open your favorite compressor as an insert on the track that needs a compressor (mono, stereo, bus, group)

2. Adjust the Threshold so that the Peaks (sudden volume changes or “spikes” that need to be reduced) will surpass the Threshold narrowly. Unless you want to compress instruments that there’s no problem if the compressor compresses continuously, for example the bass guitar that can accept a sh*tload of compression cause it needs to be stable throughout the song.

3. Make the Ratio and the Threshold work together. Ratio is purely configured depending on the sound source but here’s some nice starting points:

Bass – 4:1 to 8:1, Drums Group:  2:1, Vocals: 2:1 to 4;1, Electric Guitars: 2:1 to 6:1

The above information are starting points don’t follow them blindly, take the initiative to experiment cause each sound is different.

4. Adjust the Attack and Release buttons, following the guidelines above. If your compressor has an Auto function on your Release button, then use it cause 80% of the situations it’s gonna work right.

But if you mix sounds with crazy peaks (sudden volume changes of the volume level) then you can easily chop off these peaks with really fast attack, even if it’s only 1ms or 3ms.

Use fast attack on Mono Tracks with Instruments/Vocals with sudden peaks and slow attack on Group Tracks, where the compressor here plays the part of  “Glue instruments together” rathen than “Work for a more stable volume between the louder and the quieter parts”.

Always, Keep your ears open and hear the changes that you make!

5. Use the Make-Up Gain to get the volume level back to where it was. The compressor’s role is not to give volume. It is to give back the volume that the compressor reduced so that when we bypass the signal we hear the before and after sound with the same volume level.

If you have for example 6db Gain Reduction then you need to add 6db Make-Up Gain.

6. Make sure the volume levels between the sound with and without the compression to be the same. You may have compressed the signal in an awful way but your ears would think that you did a nice job because of the louder volume. Our ears always think that louder is better.

So for this reason, keep the volume the same NO MATTER IF THE COMPRESSOR IS ENABLED OR DISABLED.

Written By:

Jeff Peaks aka Mr Peak Level

#PeakLevelWitNoDistortions