hello
I'm using the [vcf~] filter quite a lot these times
of course, when you raise the Q factor, as the peak narrows, the volume decreases
I would like to set up something automatic that tunes automatically the output volume of vcf~ in function of Q
For example, something simple like output_lev = input_lev * k * Q (if Q > 0) where k is a multiplicative factor I don't know about this "k" factor ; I could find it empirically, but isn't there a more serious way of determinating it ? (assuming the input signal is white noise)
Also, when Q = 7, for example, what is the bandwidth of the filter ?
thanks a lot for your help
of course, when you raise the Q factor, as the peak narrows, the volume decreases
I would like to set up something automatic that tunes automatically the output volume of vcf~ in function of Q
i wrote a small abstraction that changes the takes to signals as inputs and changes the volume of the first signal that it's about the same as the second signal ...
this seems to be what you are looking for ;-)
(note that it's using an envelope follower that uses a blocksize of 8192, so with a samplerate of 44100 the abstraction won't be able to react to attacks that are shorter than about 50 ms ... it's also using a linear adjustment of the factor with a ramp of 200 ms, you might want to change that if you change the queue very fast)
cheers...
Tim mailto:TimBlechmann@gmx.de ICQ: 96771783 -- The only people for me are the mad ones, the ones who are mad to live, mad to talk, mad to be saved, desirous of everything at the same time, the ones who never yawn or say a commonplace thing, but burn, burn, burn, like fabulous yellow roman candles exploding like spiders across the stars and in the middle you see the blue centerlight pop and everybody goes "Awww!" Jack Kerouac
hi Tim,
jyust for fun -- two similar solutions are in the archives, (a post from 11/17/01, with the subject "an attempt to balance~ the shame")
Krzysztof
Tim Blechmann wrote: ...
i wrote a small abstraction that changes the takes to signals as inputs and changes the volume of the first signal that it's about the same as the second signal ...
I found (empirically) a very simple solution for getting a constant level when you change Q
see attached file : "vcf-Q-level-balance.pd"
I don't know if this solution is "good" or not (it doesn't take the cutoff frequency as a parameter, for example), but at least it's a good approximation (the level looks constant on the visualisation software of my sound card -- and also hearing it)