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[Doepfer_a100] Standard OTA-Filters, was: Octave Cat Filter

2005-06-13 by Florian Anwander

Hi Dieter

> The original Octave Cat filter is nothing but a standard 24dB filter based
> on four OTAs (CA3080). I cannot see why it shoud sound so extraordinary. 
I have/had the Formant VCFs, which are based ont the standard CA3080 
schematic.
- The 12dB Version is really something on its own and I like it very 
much (isn't it the same as in the Oberheim SEM module?).
- I never liked the 24 dB version of the Formant Filter. Assumingly this 
dedicated implementation was not good. But there are a lot of synths 
which sound really great(!) with this filter type: at least different 
Roland Synths like the SH-2, Jupiter 8, Roland System 700 (maybe some 
are with BA662 + FET-buffer instead of the CA3080 + OpAmp-buffer).

So I think it is worth a test.

> published 12dB filter with two CA30380). I thought we have enough filters.
> But who knows .....
I think, if you find a catchy name like "Jupiter-Filter" or "SEM-Filter" 
its reason enough for many customers to buy it ;-)))

Florian

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