[sdiy] Famous Fixed Filters - FFF PCB ?

[JH.]

This looks interesting all by its own - a steep filterbank, and an 
alternative to the omnipresent Moog and EMS filter banks, maybe.

It's hardly a small filter to be included in a collection, though ...
But as a standalone circut, why not.

JH.

----- Original Message ----- 
From: "Derek Holzer" <derek at umatic.nl>
To: "JH." <jhaible at debitel.net>
Cc: <synth-diy at dropmix.xs4all.nl>
Sent: Sunday, November 25, 2007 2:35 PM
Subject: Re: [sdiy] Famous Fixed Filters - FFF PCB ?


Hi Juergen,

JH. wrote:
> Hi -  I've been thinking about PCB projects for 2008.
>
> What dou you think about a collection of "Famous Fixed Filters"?

I recently had a brief chance to play around with one of the only
existing Subharchord synthesizers:

http://en.wikipedia.org/wiki/Subharchord
http://www.subharchord.com/index-Start.html

The filter bank alone was to die for: 14 extremely steep 96dB formant
filters!

http://www.subharchord.com/sub_frameset/gebrauchsanweisung/Melfilter.html

I don't know if they are exactly fixed, however. The documentation seems
to indicate that they have a range of 200 Hz on the lowest end to 2000
Hz on the highest end:

Nr. 1: 200 ... 400 Hz
Nr. 2: 400 ... 625 Hz
Nr. 3: 625 ... 875 Hz
Nr. 4: 875 ... 1170 Hz
Nr. 5: 1170 ... 1550 Hz
Nr. 6: 1550 ... 1970 Hz
Nr. 7: 1970 ... 2420 Hz
Nr. 8: 2420 ... 2900 Hz
Nr.: 9 2900 ... 3450 Hz
Nr. 10: 3450 ... 4000 Hz
Nr. 11: 4000 ... 5000 Hz
Nr. 12: 5000 ... 6500 Hz
Nr. 13: 6500 ... 8000 Hz
Nr. 14: 8000 ... 10 000 Hz.

Still, if there's any filter from history that I would like to own,
this would be my "classic" request.

best,
d.

-- 
derek holzer ::: http://www.umatic.nl ::: http://blog.myspace.com/macumbista
---Oblique Strategy # 125:
"Only a part, not the whole"