Keith Everette Smith

Producer, Songwriter, Multi-Instrumentalist, Music Director

EQ... pre or post compression

When engineers get together we talk about silly recording stuff. It’s goofy and silly and if I pretend I’m listening in on the conversation rather than participating in it, I find myself laughing hysterically at how much of a total dork I am. But, that’s what happens when you love what you do… you don’t care how much of a dork you are. In fact, being a dork about your craft will make you better at it. Because you care!

In those geeky conversations we’ll often talk about our techniques for EQ and COMPRESSION. One frequent topic is whether or not to EQ pre or post compression. Meaning, whether or not we choose to EQ before a compressor (pre) or after (post). Everyone has their techniques and no one is wrong. I have a very basic way of approaching this. Hopefully these guidelines will help you. Feel free to reply with your techniques for this is in no way a holistic approach. I am still developing my ear too.

WHAT COMPRESSION DOES…

We all know that compression controls dynamics but what you may not be clued into is how it affects the sound. In addition to dynamic control compression also does 2 things…

emphasizes dominant frequencies and rolls off the top end.

1) It’s important to note that compression is going to overemphasize the dominant frequencies in the instrument you are compressing. The more extreme the compression the more extreme the result. This is important to know because if there is an odd frequency in your bass guitar and you’re really smashing it with a limiter, you may end up with a very odd sounding instrument. You may have guessed what you should do… PRE EQ.

If the compressor is doing odd things to the sound of the instrument, do some PRE EQ carving to shape the instrument so the compressor has a more even sound to compress. (TIP, always compare what it sounded like before you tweaked it.)

2) You are almost always going to lose some top end fidelity when compressing. For this reason (and others) many people choose to EQ post compression to try and make up some of the sound lost in the high frequency range caused by compression. Some people compress post EQ almost all the time to try and make up for compression. Not a bad idea.

This topic came up when I was discussing Chris Lord Alge’s techniques for mixing. He has a very over-the-top compression sound and he is also known to HEAVILY EQ things. Well, you’ll notice if you have the CLA Waves SSL Bundle that all of his presets use EQ before compression. The presets boast a lot of EQ and a lot of compression.

Now, the SSL EQ’s are extremely aggressive. They have a bite that is coveted by many engineers. What I’ve noticed is that you can use this aggressive EQ and the compressor will take off some of the bite. You would also need to add a lot of HF EQ because of how much the compressor is affecting the sound. I guess what I’m getting at… CLA can heavily EQ because he runs the EQ in PRE and then compresses so heavily (dulling the EQ and making it not so extreme). This is part of CLA’s massive sound.

Now I don’t subscribe to this all the time. I think I’m a bit less extreme than CLA is… and he’s a freakin’ beast and makes amazing music. To draw a comparison feels pretentious at the least… so I don’t :) I do find it useful to use both techniques for different situations.

As you are learning, try being aggressive with compressors and EQ in order to learn the sound of your gear BUT I would encourage you that LESS is definitely more. Your more natural sounding mixes will be loved… I promise. You can slowly work your way into more aggressive mixing as you learn where “too far” is. You’ve gotta learn what real instruments sound like and how to finesse them into musical submission. It takes a long time. I’m still working at it!!

Hope this stuff helps!!