Sidechaining: what are all the tricks of the trade in mixing?

[Googlyman]

so???

[Sotsirc]

The basics:
The sidechain is the circuit of the compressor that "sees" the material being worked on. Normally that would be whatever you feed the input of the compressor because that's what you want it to work on.
However, if you feed the sidechain something else, the compressor will think that this is the material that need leveling etc. It will then be completely blind to the material you're feeding the input.

So, you can feed the sidechain a heavily eq'ed version of the material to make it react to specific frequencies more than others. This way you will never hear the eq'ed version but the version you've fed the input will be compressed as if it were the eq'ed version. Makes sense?

Now, you can also feed the side chain something completely different. The classic is putting the compressor on the bass and feeding the kick drum to the sidechain. That way the bass will get compressed (ie the volume will get lower) every time the kick drum hits. This way you can avoid clashes as well as you make the kick drum seem more powerful (especially if you apply this technique on synths etc).

Another common way to use it is to compress the guitars whenever the vocals come in. Of course you always have to make sure the compressor is set appropriately in terms of threshold, ratio, attack etc. Experiment. Use those ears.

[Andy Warren]

Originally Posted by Sotsirc

The basics:
The sidechain is the circuit of the compressor that "sees" the material being worked on. Normally that would be whatever you feed the input of the compressor because that's what you want it to work on.
However, if you feed the sidechain something else, the compressor will think that this is the material that need leveling etc. It will then be completely blind to the material you're feeding the input.

So, you can feed the sidechain a heavily eq'ed version of the material to make it react to specific frequencies more than others. This way you will never hear the eq'ed version but the version you've fed the input will be compressed as if it were the eq'ed version. Makes sense?

Now, you can also feed the side chain something completely different. The classic is putting the compressor on the bass and feeding the kick drum to the sidechain. That way the bass will get compressed (ie the volume will get lower) every time the kick drum hits. This way you can avoid clashes as well as you make the kick drum seem more powerful (especially if you apply this technique on synths etc).

Another common way to use it is to compress the guitars whenever the vocals come in. Of course you always have to make sure the compressor is set appropriately in terms of threshold, ratio, attack etc. Experiment. Use those ears.

Thanks for this great description.

[Thuneau]

Here is one of the most powerful tricks of side-chaining. Feed the program to the side-chain in real time, but delay it slightly to the input. This will let you compress your audio more aggressively while avoiding pumping artifacts. Basically your gain reduction will take place slightly ahead of the audio that needs to be reduced in level. It's like look-ahead peak limiting, except you can dial it in with longer look-ahead times and true RMS detection instead of peak detection.
With this trick and a bit of HP filtering of the side chain signal you can turn a generic compressor into a very smooth sounding one.

[Fezzle]

For slamming house/techno dance tracks, especially in dense mixes a common trick is to set up a compressor on synths/pads/keys etc, and sidechain the compressor to your kick drum, set the attack and release to instant, and reduce to taste, whenever your kick sounds everything else dips for a split second and you as long as you dont over do it it can bring out the beat more for less voltage aka LOUD AND PUMPING

[SochiTag]

I bookmarked these two video a few weeks ago - which show something a tad different with sidechain compression.

Sidechaining Tutorial - YouTube
White Noise Sweep Tutorial (in Logic) - YouTube

[Sotsirc]

Originally Posted by Andy Warren

Thanks for this great description.

Glad to help

[Bassmankr]

In line with what has already been said above since what you feed the side chain does not go out of the compressor as audio and is only fed to the compressor's detector you can pick up a cheap used $40 multi-effects unit that has both delay and EQ just for side chaining duties. ITB out to hardware compressor you would just use an additional clone channel with delay and EQ used for this however you would use up an additional DA converter channel.