Modulate filter frequency
I would like to moulate the cutoff of a filter created with the filterdesign + cascade method.
Now of course thats easy with floats but there appear clicks.
I thougth it must be possible to modulate it with a signal, but couldn’t figure out how?
Thanks for any pointers!
Is this not possible? I must be overlooking something.. please..
Not an expert, but i think you can find everything you need right here: http://cycling74.com/2008/07/15/lfo-tutorial-1-the-zen-of-the-silent-patch/
The problem is really that i don’t see a way to use filterdesign(which hasn’t existed when this great tutorial was written) and change the cutoff frequency at sample rate.
Thanks anyway, still hoping that i miss something here.
There are a couple of things here – the first one being (if I recall correctly) that the dictionary stuff that filterdesign passes to the cascade~ object is filter coefficient-based – so there’s not going to BE a "cutoff frequency" value, as such. That’s always been true for the cascade/biquad objects, attested to by the existence of the tried and true filtercoeff~ object from long ago. That said, it’s pretty clear that the filtercoeff~ object does allow for signal-rate manipulation, in which case I’d wonder if perhaps mucking about with the dictionary data structure being passed to the cascade~ object might be one way to approach the problem. I wouldn’t be surprised that it might be hairy, but you *do* have access to the dictionary data structure that the filterdesign object is pumping out via the dict object, don’t you?
thanks. wouldn’t it be great if one could design arbitrary filters and having a filtercoeff manipulation object to modulate the cutoff?
I mean i really think i understand the problem here but it seems like i would have to kind of reverse engineer the filterdesign stuff.. maybe i am wrong here but … consider it a feature request maybe.
Thinking about it again, i cant understand why this isn’t somthing a lot of people would like to be able to do in a fast and simple manner. Filterdesign would just get so powerful. doesn’t one need filters that don’t click when the cutoff is changed most of the time?
i agree. the crackling when adjusting frequency is so messed up….
I agree that this could use some options for at least getting click-free filter cutoff movements.
in the meantime, check out Peter McCullough’s filters here:
the moog one is particularly tasty, and eminently hackable! :)
but you wont get click free movements anyway with a biquad – as soon as people have the option to use signals to control a biquad, they are in danger of explosions more than before. :)
maybe i dont get the original post, but i think the best was is to convert numbers to signal for a biquad using ]line~ 35] …
Maybe i wasn’t clear enough..sry.
Controlling biquads cutoff is no problem at all, since it works click-free with filtergraph or even better, one can use an "audio" signal for the filtercoeff- objects cutoff (don’t know if this exists in max 4 since you are 4 roman right?btw thanks for the remapping abstractions!)
My problem is kind of max 6 specific since i miss the possibility to change the cutoff of the new filterdesign object without clicks, which makes me sad.
i usually use a hidden filtergraph when i need "filtercoeff" in OS9 – but there is also that third party double-precision hr.filtercoeff~ MSP object – which does the same than the cycling one from max 4.5 and above – if you just leave the second output pair alone.
that, and the percolate MSP mtof~ belong to the few third party objects i accept.
seems i was missing the difference between "filterdesign" and "filtercoeff", maybe you should type louder. :)