what can i do with two bandpass filters? [BMC32 blended BP]

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htor
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what can i do with two bandpass filters? [BMC32 blended BP]

Post by htor » Tue May 04, 2021 6:31 am

somebody gave me 2 identical Barton Blended Bandpass PCBs the other day.
i'm wondering what i could do with these and if i could possibly combine them in an interesting way to have a dual filter module of some kind?

http://www.bartonmusicalcircuits.com/ba ... index.html
Screen Shot 2021-05-04 at 13.21.27.png
my initial thoughts:

1) in series: filter1 simply outputs into filter2. filter2 input could be normalled to it, so in case i plug something in there i have two separate filters.
2) in parallel: filter1+2 outputs mixed together (is that how parallel works?). this stage could be an attenuvator to get boost or cut in response.
3) both?
4) i'd really like CV control over these, but i'm not sure how that would work out :?:

ixtern
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Re: what can i do with two bandpass filters? [BMC32 blended BP]

Post by ixtern » Tue May 04, 2021 6:55 am

Serial connection is rather risky - you may hear almost nothing if filters are not in the same band.
Parallel has many possibilities - different control to each filter (two envelopes or one envelope and one LFO or tracking notes).
Or one control for parallel and different filter settings.
In parallel you may connect as many BPFs as you want.

jorg
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Re: what can i do with two bandpass filters? [BMC32 blended BP]

Post by jorg » Tue May 04, 2021 2:19 pm

ixtern wrote:
Tue May 04, 2021 6:55 am
Serial connection is rather risky - you may hear almost nothing if filters are not in the same band.
Parallel has many possibilities - different control to each filter (two envelopes or one envelope and one LFO or tracking notes).
Or one control for parallel and different filter settings.
In parallel you may connect as many BPFs as you want.
There is one nice thing you can do with series connection. Set them to a Q of about 6.5, and the frequencies about 20% apart. You get a nice rectangular-ish spectral shape, with flat top and steep skirts. It takes a decent-sized chunk of spectrum.

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