As you’ve probably guessed, the place to start is the sound of the instrument itself. If that doesn’t sound the way you want it, it’s going to be awfully hard to convince it to sound that way later with lots of EQ. But for the purposes of this article, we’ll assume you know that, and you have your instruments dialed in the way you want them. We’ll also assume that it’s obvious your mic selection will influence the sound of the track, as will the use of high pass filters built into many mics themselves (technically still an equalizer). But aside from all that, here are some additional ways to shape your sound without EQ.
Use the mic’s pickup pattern to your advantage. Often, placing a mic off axis to the instrument sounds better than dead on. Rather than point a mic straight at a speaker cone on a guitar amp, for example, try angling the mic a bit so it points slightly away from the speaker. You’ll often find there’s less mud that way, and the track sits better in a mix with bass and drums.
Make good use of bass proximity. A mic in any pickup pattern other than omnidirectional will have a bass bump as you move close to it, while the low end will start to drop off as you move it farther away from the source. Want more low end? Move the mic closer to the source. Do the reverse for less low end.
Take advantage of comb filters. Whenever you have two or more mics on one source, the signals and the reflections hitting the two mics will combine with each other and cause some frequencies to be cancelled or attenuated and others to be amplified — an effect known as a comb filter. You can’t get rid of comb filtering entirely; whenever you combine an original sound source with its reflections, or two different miked signals, comb filtering is inevitable. The question is, does the effect sound good or bad? Placing the mics in the “wrong” spot relative to each other may result in a lot of cancelled fundamental frequencies, producing a thin, incoherent sound. A comb filter that amplifies the instrument’s fundamentals, on the other hand, will create a more powerful and cohesive sound.
Normally you look for the “sweet spot” when using multiple mics — the spot where each mic sounds good on its own, and the combination is phase coherent and sounds solid. But sometimes, you actually want to create a thinner, weaker sound if the instrument is meant to be a background pad or ambient coloration. I’ve often used this technique to make an organ track seem to float on top of a mix, for example — organ can be overbearing at times and seem to hog the whole mix, but using two mics on it and placing them so there’s a bit of phase cancellation can give it a spacious, ethereal quality that sits very nicely in the mix.
Or you may want to bring out certain overtones in the instrument by creating a comb filter that amplifies those overtones. It’s not necessary to do a lot of math and figure out the exact distance the mics must be from one another to achieve this (although you ...