Crumar Musical Instruments User Group.

Hi guys,

I've got a Crumar Symphonizer and all of the G# notes have gone dead. 
Any idea how to fix it? It was working fine up until now.

Thanks,
dedric

Assuming that a Symphonizer uses organ-type divide-down technology (a 
la Polymoog), then this sounds like one of the boards (or chips) (the 
one controlling the G#s has passed away due to old age.

You'll need schematics to work this out, then hopefully a simple 
board (or chip) replacement would sort it out. Assuming they are 
available.

However, don't quote me on that! I may well be barking up the wrong 
tree. Or simply barking.

I do however know someone who fixed a similar problem on a Polymoog 
by simply replacing the right chip.



--- In crumar@yahoogroups.com, "montamusic" <dedricmoore@...> wrote:
>
> Hi guys,
> 
> I've got a Crumar Symphonizer and all of the G# notes have gone 
dead. 

> Any idea how to fix it? It was working fine up until now.
> 
> Thanks,
> dedric
>

Thanks for the tip. I found a guy here in Kansas City that worked on 
Crumars when they came to the States 30 years ago. I'm taking it to 
him next week.

Cheers,
Dedric

--- In crumar@yahoogroups.com, "rakky" <pargroups@...> wrote:
>
> Assuming that a Symphonizer uses organ-type divide-down technology 
(a 
> la Polymoog), then this sounds like one of the boards (or chips) 
(the 

> one controlling the G#s has passed away due to old age.
> 
> You'll need schematics to work this out, then hopefully a simple 
> board (or chip) replacement would sort it out. Assuming they are 
> available.
> 
> However, don't quote me on that! I may well be barking up the wrong 
> tree. Or simply barking.
> 
> I do however know someone who fixed a similar problem on a Polymoog 
> by simply replacing the right chip.
> 
> 
> 
> --- In crumar@yahoogroups.com, "montamusic" <dedricmoore@> wrote:
> >
> > Hi guys,
> > 
> > I've got a Crumar Symphonizer and all of the G# notes have gone 
> dead. 
> > Any idea how to fix it? It was working fine up until now.
> > 
> > Thanks,
> > dedric
> >
>

--- In crumar@yahoogroups.com, "montamusic" <dedricmoore@...> wrote:
>
> Hi guys,
> 
> I've got a Crumar Symphonizer and all of the G# notes have gone dead. 
> Any idea how to fix it? It was working fine up until now.
> 
> Thanks,
> dedric
>
 Yeah I just worked on a symphonizer the other day and it's the
earliest one I think Crumar made isn't it?  Older looking design than
the stringman etc.  Anyway I think it uses a MK50242 TOS..I can't
recall. Multiman has the MK50240 which is more common.   I should have
written more info on it while I had it here.  I seem to recall the
SAJ110 dividers but those would generally be bad if you were missing
sub-octaves.  If it's all the notes of a type them most likely the Top
octave synth chip (TOS) or discrete oscillators in units that have 1
for each note (12).  Like combo organs or the early Roland EP10 piano
etc.  But all the crumars used TOS chips I believe.  -bob

PS and I should have said to trouble shoot you can use a headphone amp
(nice because small and a volume control you can thumb operate as you
are probing around often.  I built a custom one for this purpose)  and
just hook a probe to a jack that goes into it.  THen you can ground
clip onto the ground of what you are working on and put the probe on
various pins of the TOS for instance and you can hear all the
frequencies there.  If one is missing or distorted it should be
obvious that you then have a bad TOS. -Bob

Yes. It's an early model that was released here in the US, or so I'm 
told, that didn't do well and was discontinued. Mine is A/77. 

It's been invaluable on our last recording and I'd hate to lose it. 
I'll pass on the tips to the service guys. you've given me a much 
better understanding of how this thing works. 

Many thanks,
Dedric


--- In crumar@yahoogroups.com, "Robert Weigel" <sounddoctorin@...> 
wrote:
>
> --- In crumar@yahoogroups.com, "montamusic" <dedricmoore@> wrote:
> >
> > Hi guys,
> > 
> > I've got a Crumar Symphonizer and all of the G# notes have gone 
dead. 
> > Any idea how to fix it? It was working fine up until now.
> > 
> > Thanks,
> > dedric
> >
>  Yeah I just worked on a symphonizer the other day and it's the
> earliest one I think Crumar made isn't it?  Older looking design 
than
> the stringman etc.  Anyway I think it uses a MK50242 TOS..I can't
> recall. Multiman has the MK50240 which is more common.   I should 
have
> written more info on it while I had it here.  I seem to recall the
> SAJ110 dividers but those would generally be bad if you were missing
> sub-octaves.  If it's all the notes of a type them most likely the 
Top
> octave synth chip (TOS) or discrete oscillators in units that have 1
> for each note (12).  Like combo organs or the early Roland EP10 
piano
> etc.  But all the crumars used TOS chips I believe.  -bob
>