cyamamot@castor.usc.edu (Cliff Yamamoto) (09/21/89)
Greetings! I would like some opinions from those who have used parametric equalizers before or who know about active filters. I have a parametric equalizer which I've adjusted using a RTA for my stereo. It sounds quite good but it still nags me to know that I may be causing it to sound worse due to inappropriate adjustment. What I'd like to know is: what actions to a parametric equalizer (i.e. active filter) cause the most phase shift? Is it better to have a hi Q and low boost (i.e. gain) or is it better to have a low Q and hi boost? Should I try to get by with the lowest Q possible? I know a hi Q setting (like Q=10.0) causes the eq to make pink noise sound as though it were in a wind tunnel; there is a unnatural "hollow" noise. Knowing that a hi boost and hi Q cause it to sound unnatural, I try to keep all my Q's and boosts/cuts as minimal as possible. Is this right? My actual scenerio is this: I have to cut -15dB at 800Hz because of some unusual resonance. Even with a Q=10.0 it brings down 1.2Khz and 400Hz by -6dB even though I don't need it to. On top of that, a -15dB cut with Q=10.0 makes it sound lousy. Should I widen the Q and cut by -9dB at 800Hz and boost everything below 400Hz and everything above 1.2Khz by +3dB? It seems you could spend hours with a parametric eq, even with a RTA!! Thanks for any assistance Cliff Yamamoto
bill@bilver.UUCP (Bill Vermillion) (09/27/89)
In article <5214@merlin.usc.edu> cyamamot@castor.usc.edu (Cliff Yamamoto) writes: >Greetings! > >I would like some opinions from those who have used parametric equalizers >before or who know about active filters. > >I have a parametric equalizer which I've adjusted using a RTA for my stereo. >It sounds quite good but it still nags me to know that I may be causing it to >sound worse due to inappropriate adjustment. After using parametrics in audio studio environments for years I have an opinion on them, albeit a biased opinion. I only use parametrics as a tool to help where nothing else would. As I had mentioned in a previous posting, we had even modified our 27 band speaker eqs to eliminate some of the circuits, and only used a cut mode. To properly use a parametric in a speaker equalizing environment, and I gather that is what you are doing from your posting, you would probably need to use a scope to set one parametric equal to the other. You want to treat both side of the signal EXACTLY the same, otherwise you start ruining the stereo imaging. Parametrics are virtually impossible to set up the same way twice. A good rule to use in eq'ing things is to use cut only, and not boost. Much kinder to the ear. Only boost if ABSOLUTELY neccesary. The above are my opions only, because I have observed that if you take 3 engineers, and 3 producers, you will come up at least 9 ways of doing things, each of which will be THE ONLY RIGHT WAY!!!! :wq -- Bill Vermillion - UUCP: {uiucuxc,hoptoad,petsd}!peora!tarpit!bilver!bill : bill@bilver.UUCP