I tried your suggestions. I still only hear the distortion from OSC 1. I also hear it with
either saw or pulse waves (yes, the pulse width knob changes the sound). Panning the
voice makes no difference. I did notice that when I first power on the synth, I don't hear
the distortion, but as it warms up the distortion becomes more and more evident.
Hmmmmm...

I really appreciate your help. Any other suggestions I have access to a volt meter...

Jonathan

--- In oberheim@yahoogroups.com , "nelsonj_sce" <nelsonj_sce@...> wrote:
>
> Before you said if you changed the voice board you still had the same
> problem. If that is the case, the problem is not on your voice card
> so don't try changing parts on the voice card.
>
> You say the problem it is only with OSC1. So if you ONLY have OSC1
> on you hear distortion, but if you ONLY have OSC2 on there is no
> distortion (make sure OSC2 is at full level), correct If the
> problem really is with just OSC 1, see the next paragraph. If the
> problem only happens when both OSCs are on, the output level is
> likely too high. Each voice passes through a passive (i.e. resistor
> divider with a pan) before the final output stage. The pan was the
> most likely cause, but you already tried that. Try panning the voice
> hard left and hard right. Do you have the distortion in both
> positions
>
> Does the problem happen on both the Saw and the Pulse shapes Does
> the Pulse Width change as you spin the PW knob If the problem is
> only with the Pulse Wave I have some ideas.
>
> Let me know what happens.
>
>
> --- In oberheim@yahoogroups.com , "jringmrath" <jringmrath@> wrote:
> >
> > I tried panning the distorting voice card and cleaning the pots- it
> didn't help. I do only
> > hear it when I have OSC 1 engaged - with just OSC 2 I don't hear
> the distortion. The weird
> > thing is that I tried replacing the Curtis 3340 for OSC 1 and I get
> the same distortion, so I
> > don't think it is the chip. Any other thoughts
> >
> > Jonathan
> >
> > --- In oberheim@yahoogroups.com , "nelsonj_sce" <nelsonj_sce@> wrote:
> > >
> > > As for the distortion, try panning your bad voice and see if that
> > > helps the problem. Also clean the pan pot with some component
> > > cleaner.
> > >
> > > As for the "ghost" note...I have to think more about that.
> > >
> > > --- In oberheim@yahoogroups.com , "jringmrath" <jringmrath@> wrote:
> > > >
> > > > I have an 8-voice OBXa and have a couple of nagging issues I
> > > haven't been able to resolve.
> > > >
> > > > First, I seem to get some slight distortion from voice board
> #8.
> > > If I move the board to
> > > > another location, it sounds fine. If I move a known good voice
> > > board to the #8 position I
> > > > get the same distortion. It is most obvious on the organ-type
> > > sounds. I have been using
> > > > it as a 7-voice until I can track down the problem.
> > > >
> > > > Second, if I play the chord "G,C and Eb" in the middle octave
> of
> > > the keyboard, it also
> > > > sounds the "E" below the G. Needless to say, this can be
> > > annoying! Must be something
> > > > having to do with the keyboard scanning, but I don't know what
> > > exactly. The double mode
> > > > also doesn't seem to work 100%. Maybe a related issue
> > > >
> > > > Any thoughts on what might be causing these and how to fix
> them I
> > > have the schematics,
> > > > but I don't really know what I'm looking at since I'm not a
> tech.
> > > >
> > > > Thanks for any help or advice!
> > > >
> > > > Jonathan
> > > >
> > >
> >
>