Subtractive vs. Additive EQ...

[BilltheCat]

How do you handle EQing when you're wanting to accentuate a particular range? For instance--say you want to throw the bass line out front, and really push the 800hz range. Would you be more inclined to go +4db, or would you simply *reduce* the other ranges, such that the 800hz range was at 0db, and everything else was -4db? Would it change your opinion if I said +-8db? Everthing I've read seems to indicate that Subtractive is the preferred method. Is this just one of the exceptions?

It seems like I'm adding a large amount of noise to do it at +4db, but for the life of me, don't see a smart way of reducing everything else. Perhaps I'm overlooking something.

I'm using EMU0404 and Cubasis VST 4 for what it's worth.

Cheers,

 

[Chibi Nappa]

Here's how I do it:

When I want to accentuate a frequency, I use addative EQ. However, before I do that I stop and think "do I really want to accentuate that frequency?" Often times the answer is to subract EQ from a different track to make the frequency in the orriginal track stand out.

Other times I'll hear a track that sounds dull, and insead of boosting highs I cut a low frequency. This doesn't mean cutting all frequencies aside from one specific high frequency. Just a little cut in one area can brighten the track up.

The reason people say 'cut not boost' is that you can usually hear EQ 'artifacts' (phasing sounds and nastiness like that) more when you boost, especially if you have cheap EQ like me. In general, you shouldn't run into problems boosting 5 db or less, and if there is a problem you'll hear it. In the end if it sounds the way you want it to sound, you can do it.

 

[mixsit]

Here's another angle. Sometimes I try to minimize what's wrong first (first priority being a cleanup stage and to do the least amount of damage), then reevaluate. In your example of wanting more 'throat on the bass tone, I'd want to be sure the lower shelf (or shape) didn't need trimming before adding the 800Hz.
Otherwise, I would agree you would do a narrow push in the middle before pulling two shelves down on either side, if for no reason than it uses one filter instead of two.. again, the least processing going on being a factor.
Wayne

 

[LRosario]

Additive vs subtractive really dosn't make much difference as long as any given engineer is aware of the effects of both.

I personally rely solely on subtractive EQ and I'll tell you why.

You have to understand that with EQing, there comes phasing issues. When you start taking away from, or adding too much of, you're basically changing the characteristics of the recorded sound all together. So the less you do on EQ, the better it will be.

Additive EQ tends to add volume. Think about it, all you are doing is increasing the volume of a certain frequency range. That's ok if you understand exactly what you are getting. But most of the time, people tend to forget that fact and overdrive (clip) the wave.

subtractive EQ really dosn't "morph" the sound as much as additive EQ. You're cutting a piece of the pie away, not adding cherries. Think of it as sculpting. You start with a block and you slowly and carefully chip away the pieces to create your work of art.

From that experience, I usually tend to boost frequencies only when I intend on changing the sound altogether.

 

[masteringhouse]

When you want to add a given range of frequencies use addititve, when you want to reduce a given range subtract.

It's that simple.

Phasing issues can result from both additive and substractive EQ unless you are using a linear phase EQ in which case there is NO phase distortion. In some cases phase distortion can be desirable and is one reason why some people prefer analog EQs over digital.

 

[Bulls Hit]

Another thing to bear in mind is that, to the human ear, an eq cut is less noticeable than an eq boost