[sdiy] [OT] Analog synths with 2 pole filters

[cheater cheater]

It's not like linearity is even desirable in a synth filter.

Many synths have diode clippers in the feedback path in order to
change the loudness of the resonance vs the rest of the response, for
one thing. It's very practical.

Cheers,
D.

On Thu, Feb 21, 2013 at 7:58 AM, Andrew Simper <andy at cytomic.com> wrote:
> This is a repost with [OT] in the subject, sorry for not adding that
> in the first place.
>
> Hi Guys,
>
> I'm having a discussion with a friend who said that "most analog
> synths with 2-pole filters won't self-oscillate". I know quite a few
> analog synths with 2-pole filters that do self osc, so I thought I'd
> write up a list to shed more light on the situation.
>
> Can you guys please help me fill in the considerable missing gaps by
> naming some more and/or correcting what I already have? I know that
> you can make ladder / cascade / svf / sallen key 2-pole analog filters
> that self oscillate, this is really just seeing how most production
> synths have been designed.
>
> Analog synths with 2 pole filters that self oscillate
> --
> Korg MS-10 / MS-20 / Monotron / Monotribe (sallen key)
> Steiner Parker Synthacon (sallen key)
> Oxford Synth Company OSCar (svf)
> Electronic Dream Plant Wasp (svf)
> Oberheim Xpander (cascade with summed taps)
> Formanta Polyvoks (svf)
> Arturia Minibrute (sallen key)
> Elektron Analog 4 (svf)
> Dark Energy v2 (svf)
> Future Retro XS (svf)
> ARP Odyssey whiteface mk1 (svf)
> Oberheim OB-Xa (svf)
> Oberheim OB-8 (cascade-ish - need to adjust res trimmers)
>
> Analog synths with 2 pole filters that don't self oscillate
> --
> Oberheim SEM (svf)
> Roland JP6 (svf)
> Alesis A6 (svf)
> Prophet 8 / Prophet 08 (cascade)
> Yamaha CS 80 / CS 40 (svf)
>
> Thanks!
>
> Andy
> --
> cytomic - sound music software
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