[sdiy] best soundign vco design?

[jeff brown]

----- Original Message ----- 
From: "St Eric's..." <sainteric at piramiden.demon.nl>
To: "Dana Scott" <danas at egosys.com>; <synth-diy at dropmix.xs4all.nl>
Sent: Sunday, June 13, 2004 3:35 AM
Subject: RE: [sdiy] best soundign vco design?


> Well, Dana,
>
> I am interested!
>
> Eric van Baaren.

I'll take two.

Jeff Brown

> _____________________________
> http://www.piramiden.demon.nl
>
>
>
>
> -----Oorspronkelijk bericht-----
> Van: owner-synth-diy at dropmix.xs4all.nl
> [mailto:owner-synth-diy at dropmix.xs4all.nl]Namens Dana Scott
> Verzonden: zaterdag 12 juni 2004 13:26
> Aan: Roy J. Tellason; synth-diy at dropmix.xs4all.nl
> Onderwerp: Re: [sdiy] best soundign vco design?
>
>
> I have seen at least one site on the 'net with schematics of the potted
> modules
> posted.
> Early potted modules were completely encased in epoxy. By the time I
started
> working at ARP (Feb. 1974) they were potting them in soft RTV rubber with
a
> thin
> layer of epoxy on top. These were frequently cracked open and repaired.
The
> Avatar E' module was an exception. All of those were hard potted... Well,
> not
> _all_ of them. I have one that is not potted.
> Somewhere in my files I have a 1:1 film negative for a 4027-1 VCO.  I
don't
> think board houses will accept films without NC drill info anymore. On one
> of my
> old computers I have a CAD board layout I did of one of the modules, ring
> mod I
> think.
> I was thinking of running off a batch of 4109 filter modules. The 4109 is
> the
> filter used in the Centaur prototype. It is a VC state variable filter
with
> low
> pass , high pass, bandpass and notch outputs, It uses the same basic
filter
> section as the 4075 and 4072 filters and has voltage controlled resonance
> too.
> Do you think it would be work my effort to produce a batch of these?
>
> -Dana
>
>
>
> ----- Original Message ----- >
>
> > Any of you guys know if the details of those potted modules that ARP
used
> to
> > use ever got out?  Just curious,  mostly...
> >
> > Wanna talk about "fat" sound?  Best I ever did was to have _THREE_ 2600s
> > finished up at one time and still on the bench.  So of course I patched
> 'em
> > together... :-D
> >
>
>
>