Maxx VCS - Changes

[Tony Allgood]

I like the DG series from analog devices, rather than the 4016/66. Separate
analogue and digital supplies. The analogue can run off +/- 15 and the
digits from +5V. The DG-271 is rather nice and it has very low charge
injection as well. There is a AD part in my VCF module, used in the AD
envelope and in the triggerable LFO. More expensive, but easier and somehow
more elegant...

As a side issue; Soundcraft used + and - 7V5 rails for all of its 4066 audio
switching. Slightly better headroom for the analogue signals compared to +
and -5V. The op-amps were  run off - and -17V5. Take it to the absolute
limit.

Regards,

Tony Allgood, Cumbria, UK

e-mail: oakley at enterprise.net

Rack mounted Moog VCF module. Details to be found at...

http://aupe.phys.andrews.edu/diy_archive/schematics/effects/filter.html


-----Original Message-----
From: tomg <tomg at vivid.net>
To: synth-diy at mailhost.bpa.nl <synth-diy at mailhost.bpa.nl>
Date: Thursday, June 25, 1998 5:24 AM
Subject: Maxx VCS - Changes


Well that was fast maybe the fastest update my me ever. You see what happend
was....:) I know better than that I think maybe I rushed it just a
little..anyway.

The VCS-1A is now the VCS-1B. I changed the 4016 supply to +-5v this allows
audio to pass correctlly it also changes the CV capibility to a maximum of
+-
5v. You give a little you get a little. It changes the 4016 connections to
the
339s a little, also added 100K resistors from the in/out jacks to gnd for
zap
protection.

Sorry guys...it really did work like it was. It just wasn't right.

-Tom