Question about the theory behind EQing...

[Macavity224]

So I get that equalization is used to cut and increase frequencies...pretty straightforward. I was reading in a book the other day about how the point of equalization is to prevent frequencies from "fighting" each other, that is, compensating for a specific decrease in db with an increase in db on another track or vice versa. So, for argument's sake, does this mean if I had +2db on my bass track at 200hz, I should decrease my guitar track (or whatever else I happen to have) by 2b at the 200hz frequency (if they're both panned the same)? Maybe it's not as mathematical/methodical as that, but I was starting to grasp the idea of how to use an EQ, but the whole concept of

"battling frequencies" kind of threw me off and is confusing me a little bit...

 

Any clarification would be appreciated

[ski]

EQ can be used for many things: overall tonal shaping, sound design (EQ'ing something to be drastically different from the original sound), sound correction (removing hiss or rumble), as a detector for a de-esser or other type of frequency-dependent effect. The technique you posted about is called "frequency carving", where the approach to mixing uses EQ to "make room" for the sound of one instrument to pop through a mix of other instruments which have similar and competing (accumulating) frequencies.

 

o, for argument's sake, does this mean if I had +2db on my bass track at 200hz, I should decrease my guitar track (or whatever else I happen to have) by 2b at the 200hz frequency (if they're both panned the same)?

 

There is no "should". Because frequency carving is a technique, the question should really be, "is this the appropriate technique to use on a particular track with its particular sounds and arrangement?" Yes, it may seem nebulous, but there are no pat answers. There are techniques, but no rules. Everything has to do with the context of your instruments, the nature of the track, etc.

 

In keeping with your example... you have bass and a guitar that were both heavy in the 200 Hz range, and these 200 Hz-heavy parts often play simultaneously. If you want to hear each part clearly and distinctly as they play together, sure, something has to give. In this case, frequency carving might help. You'd have to make a choice as to which of those two tracks got a notch at 200 Hz, and by how much. Then you might get the clarity and separation you are looking for.

 

However, the downside is that the carved sound might end up sounding thin if it plays on its own. Frequency carving is typically done by setting an EQ in a static way. One way to avoid this would be to automate the amount of frequency notching so that when (say) the guitar plays on its own, it sounds full-bodied. When it's playing with the bass, 200 Hz is partially notched out.

 

But sometimes, clarity between instruments isn't that critical but the cumulative effect of having a prominent 200 Hz bump in both parts might be a problem for the track as a whole, in which case you might need to reduce 200 Hz in both tracks. In that case, we're not really talking about frequency carving here. That's just plain ol' EQ'ing.

 

All this assumes that you have your arrangement level balanced to begin with (or even roughly so). Only then can you really say whether or not frequency carving is the right way to go.