[sdiy] CEM VCF transconductance stage difference!

[karl dalen]

Tim!

> However the 3328 remains as an oddity, in that it is also a dedicated filter
>chip, but without the inter-stage buffering - maybe it was just cheaper than the 3320?

I would guess a yes on that!

>It is interesting to me (as someone late on the synth scene) that the 3320
>seems to have outlasted the 3328, at least as it appears to me, as there are
>still lots of filters around based on it (e.g. many of the Doepfer ones).

One speculation on this may be that the 3320 was his first VCF design,
and also became a contender to Dave Rossums even earlier 2044 design.

Being the first VCF's on a rising market P1,P5,OB8 etc, 3320 and Polysix
2044,etc. Volumes would have been quite large, way larger then the 3328
wich would have been sort of late follow'er up to the 3320. There are at
least 4 or even 5 years between these two VCF designs and the only synths
i know using the 3328 are the Bitt 99/01 and Mirage so the manufacturing
volumes would have been larger for the 3320 i suppose! 

Regarding to the P5 and P10 schematics 3320 was used at least around 1980.
P1 was manufactured in volumes of more then 10k units! It would have been
interessting to know wich CEM chip sold the most?

>Still, my idea might be intact - it will be interesting to see if anyone
>else refutes it over the next few days!

Indeed, so far it's supricingly silent! :-)

Btw, are there any other Curtis patents around?

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