Bandpass Filters

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Common Wiggler
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Bandpass Filters

Post by lie3vie3 » Sat Feb 27, 2010 1:07 pm

For my new modular system I had 4 CGS30 Bandpass Filters in mind, but because I'm running out of space and I still want to add some other modules I started thinking about what else I could do with the space.

The problem is that I don't really know what I can do with four non-controllable bandpass filters. The page on Ken Stone's site says it is good for setting up artificial resonances for virtual instruments, but I can't really imagine how that would sound. If anyone give me some information/sound examples, that would be greatly appreciated.

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Post by Hi5 » Sat Feb 27, 2010 1:27 pm

if you want bandpass filters with some control you may want to look at Fonik's ps3100 resonator project. 3 bandpass filters with cv freq control. it also has an lfo for modulating them and I am sure you could make some tweaks to get different slopes out of it and maybe even a resonance pot for each.

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Post by Luka » Sat Feb 27, 2010 5:18 pm

or try jurgen haible resonators, buchla 291

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Post by oozitron » Sat Feb 27, 2010 9:42 pm

I have a triple BP module (CGS BPs and a mixer) that is quite useful even without any CV inputs.

I like running the 808 through it, and it also makes great little percussion noises on its own. I built them with resistors that allow them to easily resonate, and just hitting them with a trigger pulse makes them ring like electro bongos :)

Someday I hope to make another one that has CV, using the CV resistor PCBs that BrideChamber sells.

Never want to come down, never want to put my feet back down on the ground

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Post by BananaPlug » Mon Mar 08, 2010 8:50 pm

For my new modular system I had 4 CGS30 Bandpass Filters in mind...
This discontinued Cynthia module is exactly that!
Obtained a used one recently and in spite of a tepid first impression (not sure why) I like them a lot. I also like the extinct Blacet Dual Fixed Filter (DF 2420). That one has HP/BP/LP switch and lot more Q but is also CV-free.
There's plenty to be done with these. I drop them into the middle of patches, often before or after a filter to bring out some aspect of the sound. Same idea as pre-emphasis before a reverb. Putting one of these upstream of a quirky filter like the Wasp can give you more control over just how it behaves at its unstable edge. The patch I'm exploring now has a ladder filter going to one of the quad bandpass channels and then to an LPG. The BP is there to accentuate the mid-highs. They're also nice for helping to separate sounds in the mix.

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