[sdiy] prophet 600 -- tough problem

[Rude 66]

both my sequential sixtrak and my crumar bit 01 rack would do this in the
past. since i gave both of them a seperate midi out from a cheap pc
soundcard, they're happy. the bit freaks out when it received midi clock and
the sixtrak doesn't lik too much midi info either.. i've 'fixed' my sixtrak
twice by simply taking some of the internal connectors off and putting them
back on ..

r./

www.bunker-records.com/rude66


----- Original Message -----
From: <IXQY at aol.com>
To: <synth-diy at dropmix.xs4all.nl>
Sent: Wednesday, June 05, 2002 1:13 AM
Subject: Re: [sdiy] prophet 600 -- tough problem


>
>  Hi,
>  If I may ask...what are the symptoms with your Prophet 600? Will it play
at
> all?  I have problems with mine sometimes when using lots of pitch bend,
mod
> wheel or playing fast solos. Sometimes notes will get lost and sometimes
> notes will "hang". I've noticed latency with the note-ons too.
>
>  I just got through doing a recording using the P600 and had to restrict
use
> of the performance controllers because of these problems. The setup I was
> using was P600 MIDI out ->Encore Expressionist -> MOTM modular, but I've
> noticed it while playing just the P600 alone. I have the latest OS
installed
> (6.08).
>
>  Has anyone else run into this problem with their Prophet 600s?
>
>  Thanks,
>   Andrew
>
>
> > From: "greg montalbano" <greg.montalbano at ucop.edu>
> >  To: <synth-diy at dropmix.xs4all.nl>
> >  Sent: Tuesday, June 04, 2002 3:46 PM
> >  Subject: [sdiy] prophet 600 -- tough problem
> >
> >
> >  > Hi--
> >  > I'm hoping to hear from anyone who has specific, detailed knowledge
of
> the
> >  > workings of the digital portion of this synth.
> >  > I have several control voltages that are completely screwed;  but the
> >  > problem is definitely upstream from the four 4051 demultiplexers*.
> >  Looking
> >  > at the outputs of those four ICs in order (on schematic "Board 4,
page 1
> >  of
> >  > 4"), the bad CVs form a pattern: 00X00XOO XOOXOOXO etc etc, where O=
a
> >  good
> >  > CV and X= a bad one.  This leads me to suspect a problem with the
data or
> >  > address lines controlling the DAC and/or demultiplexers;  can anyone
tell
> >  > me exactly what to look for and where to look?
> >  > Everything else on the synth is functioning correctly & consistently.
> >  >
> >  > Thanks.
> >  >
> >  > ~GMM