The Kawai & Teisco Analog Synths Group

--- In kawai-teisco@yahoogroups.com, "gil_we" <gil_we@...> wrote:
>
> Can you describe the problem more precisely ?
> 
> 
> 
> --- In kawai-teisco@yahoogroups.com, "jfloydhumanoid"
> <capstoneliving@> wrote:
> >
> > --- In kawai-teisco@yahoogroups.com, "gil_we" <gil_we@> wrote:
> > >
> > > We're still looking for one. The only scans that I managed to 
get 
> > was
> > > of the main CPU board... (in the Files section)
> > > 
> > > 
> > > 
> > > --- In kawai-teisco@yahoogroups.com, "jfloydhumanoid"
> > > <capstoneliving@> wrote:
> > > >
> > > > I bought it new in '84, gigged with it a few years, got 
married, 
> > & just 
> > > > dug it out of storage a few months ago.  Of course the patch 
> > memory was 
> > > > gone, but amazingly the Ni-Cd battery hadn't leaked.  I 
replaced 
> > it, 
> > > > loaded the factory patches, & it fired right up!  It's in 
great 
> > shape, 
> > > > except for a sort of 'garbled' artifact in sounds with the 
filter 
> > > > somewhat stopped down.  If the filter cutoff is all the way 
open, 
> > it's 
> > > > not present.  Anybody have a PDF (or other form) of the 
service 
> > > > manual?  I'd be happy to send $ for your trouble...
> > > >
> > >
> > Thanks for looking, Gil...  Anybody have any suggestions where I 
> > could point my scope probe & discover the origin of this 
> > unwanted 'distortion'?  I'm not afraid to troubleshoot without a 
> > schematic...you can't be timid & repair 'vintage' electronics.
> > - J -
> >
>
It sounds similar to the 'overdriven' sound of a tube amplifier 
stage, but 'garbled', and not clipped.  When the filter is completely 
open, the artifact isn't audible; only when the filter cutoff freq is 
low enough for the heavily 'filtered' sounds.  It also has an aspect 
of being periodic (having a set, repetitive pattern), suggestive of 
possibly being a result of some other signal bleeding through, but 
that's purely speculative...
In the next few days, if it's possible (and allowed) I'll post an MP3 
in the files section.  Would that be proper protol in this group?  I 
don't have much experience in this area, so please forgive me if 
it 'isn't done'.