headroom? eq cutting vs. roll off

[jugalo180]

okay, i hear that a lot of low end eats up head room. now are the engineers talking about when you have a nice mix going but you can't raise the volume to it's full potential because the low end stuff will red line the meter?

what's the difference between rolling off frequencies and cutting them? if there is a (real) difference, when will one benifit from one or the other?

thanks for any replies n advance

 

[dachay2tnr]

what's the difference between rolling off frequencies and cutting them? if there is a (real) difference, when will one benifit from one or the other?

Rolling off means to cut all frequencies above or below a certain point. So if you do a roll-off at 80 Hz, you are getting rid of all content 80 Hz and below.

A cut refers to reducing a specific frequency. So a cut at 80 Hz would primarily just effect the 80 Hz frequency and, to a lesser extent those frequencies next to it (depending on your Q setting).

Normally it is not a question of one being better than the other. It is really a matter of what you are trying to achieve. Roll-offs are most frequently used to get rid of audio content in regions outside the hearing range. So, for ex., you might roll-off at 30 Hz and below to get rid of sub-sonic rumbling. On the other hand, you would never use a roll-off at 3000 Hz, unless you are going for some wierd effect. At 3000 Hz you would use a boost or a cut, and adjust the Q depending on what you are trying to accomplish.

 

[jugalo180]

okay

so i get the picturre now. what i was doing was cutting a lot of adjacent frequencies out of range with -25db cuts so i was applying cuts in a graphic eq which would have been a roll off in a paragraphic eq. so cuts are for surgical adjustments and roll offs are for hacking.

cool, thanx

 

[dachay2tnr]

Essentially the Q setting refers to how many frequencies that are adjacent to frequency being cut are going to be effected by the cut. IOW, how "wide" of a frequency range will the cut effect. Will the cut effect a 1/2 octave worth of frequencies, a full octave, more than an octave?

On a graphic EQ the Q setting is pre-defined. You cannot adjust it. Each fader represents a specific range of frequencies. For ex., on a 31-band graphic equalizer, each fader represents about 1/3 octave. Therefore you will sometimes hear graphic EQ's called fixed-Q equalizers. On a paragraphic EQ the Q setting is adjustible.

Whenever you lower a fader on a graphic EQ you are making a cut. Conversely, whenever you raise a fader you are boosting. There is really no such thing as "roll-off" on a graphic EQ, however you could achieve somewhat the same effect by simply dropping the first 3-4 faders (or the last 3-4 faders for a high fequency roll-off) all the way down as far as they will go.

 

[jugalo180]

got it

yep, that's exactly what i was doing, i was bringing everything completely down. so i was awkwardly rolling in that sence. thanks for that helpful info. i like this place.