Subtractive Mixing for a Cleaner Mix: Part 3

 How to Save Sonic Space by Putting Less in the Mix

In Part 1 and Part 2 we discussed Subtractive Mixing and Subtractive EQ. As you learn more about using these techniques, you'll notice certain commonly occurring conflicts between instruments. Sometimes you'll encounter instruments that span more than one range. Your snare drum has both a thick low mid aspect and a bright upper-mid crack that end up competing in different families. Similarly the kick drum has a deep thud in the bass register and a crucial tap in the mids that defines your impact. In these cases the critical upper midrange band is usually narrow so you can use a deep cut with a parametric EQ set for a high Q-factor to surgically unmask the tap. Your low band will also benefit from subtractive EQ on the competing part. You can even use sidechain compression to cut those frequencies only when the kick or snare is hitting, and if you're really sneaky about it your competing part might sound exactly the same in the mix. In the studio, consider recording the left hand piano part separately from the right hand so both can be tailored precisely to fit. Vocals, guitars and keyboards always wrestle with the midrange frequencies between 1k-4k, and if your bass player prefers a grinding upper midrange they will end up competing with guitars between 750hz-1k as well.

Egos have no place in a great mix, so either those instruments will have to step out of one-another's way on key sections or be equalized to split the frequency spectrum amicably. Remember the fable of the Sun and the Wind? Battling to overcome the other players in the band is unlikely to achieve success, but imagine how easily the problem can be solved by teamwork!

"Then can't the players in the band just EQ their amps that way in the first place?"

Now you're getting the idea! You can work together with the other players in the band to craft instrument sounds that fit together like a jigsaw puzzle of interlocking frequencies. It takes discipline to adjust your amp to sound great out front even if it sounds weird on stage. Try using full-range sidefill monitors (or portable PA like Carvin Audio's S600B) to help you hear your instrument in the context of the other parts, and watch the compliments start coming back from the board and your audience. And don't limit yourself to Subtractive EQ; each musician can be responsible for their own volume in the overall mix and adjust the level on the fly as needed. This employs the ancient and perhaps mythical art of dynamics.

S600B Battery Powered Portable PA System

Subtractive Sound: A Technique that Can Work Anywhere

One of the best sounding bands I ever heard was a commercial R&B band playing in a tiny kidney-shaped lounge with only vocals in the PA and all their instruments coming off the "backline," which amounted to three tiny combo amplifiers. Their instruments were EQ'd to work perfectly together and they dynamically backed out of the soloist's way on instinct. I even saw the guitar player use his tone control to do the same thing to make room for a very low but intense clavinet solo that brought the house down! And why shouldn't your rehearsals sound fantastic, if you work as a team with the entire band to achieve a common goal.

Subtractive Mixing and Subtractive EQ work because they make sense; they are a way to make more room in the mix when something is getting stepped on, and isn't that a logical solution? What examples of Subtractive EQ have you encountered? Let us know in the comments below.

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