[sdiy] CEM VCF transconductance stage difference!

[karl dalen]

> So, I reckon it is to do with output impedance of the last
> stage: Hence by  decreasing the gm of the last stage of >the filters,
>the  output impedance is  increased which in general I take it as
>being 'a good thing', and in particular makes it work well with the 
>in-built VCA which it feeds.

>The 2045 (=2047) is a  completely  different topology altogether 
>- 2 cascaded second-order  sections, and the

Curtis latest filters was also second order with variable response.
3385, 3387 etc. btw 3328 did have a buffer and it makes sence just
as with the 3320 *standalone* VCF.
 
> Absolutely no idea how close to the mark much of this is!?

Seams like a most resonable idea/guess! Perhaps one of his
patents could give futher meat to your idea? US04514704.

Reg
KD



      __________________________________________________________
Ta semester! - sök efter resor hos Kelkoo.
Jämför pris på flygbiljetter och hotellrum här:
http://www.kelkoo.se/c-169901-resor-biljetter.html?partnerId=96914052