[sdiy] Other resonator designs

[Tom Wiltshire]

On 12 Aug 2009, at 23:52, David G. Dixon wrote:

> Ooh, I'm just listening to Scott Stites's Triple Wilson SVVCF.   
> Nice!  Maybe
> that's the one I'll have to build.  However, I'm wondering whether  
> Scott has
> found all of the many jacks and knobs on the panel to be useful  
> enough to
> justify the expense?  (That's a lotta hardware!)
>
> The two modules really have very different uses, though, don't  
> they?  The
> Polymoog one is really more about achieving a certain instrumental  
> sound,
> while the Stites one is more about sweeping spacey-ness.
>
> (I think I need 'em both!)

No, I don't think they're that different. They're both state variable  
filters. Obviously if it's only got knobs on, you can't get sweeping  
spacey-ness without sitting there twiddling knobs all afternoon. So  
Scott Stites's voltage-controlled one is more versatile. You could  
leave it set on one setting and get sounds very like the polymoog  
resonator, I'd have thought - component differences aside.

If you do build the triple wilson SVF, you might want to do a  
schematic/PCB for all three filters on one board, rather than use  
three MFOS boards. The MFOS SVF design uses 2 LM13700's, but half of  
one of them isn't used, which makes three wasted VCAs in total.

T.