All about the Roland Jupiter-series

-----Original Message-----
From: Scott Fiorenz [mailto:sfiorenz@...] 
Sent: Thursday, June 01, 2000 1:04 AM
To: Kevin Lightner
Cc: Analogue Heaven
Subject: Re: [AH] Jupiter-6 Service Question!


hey, while u guys are commening on the JP6 stuff
could u shed some light on my ob8 prob? :)


ok, here it is:
With both oscillators off, and keys are played-
hiss still bleeds through the outputs!
& the oscs still sound but at greatly reduced volume..
:0/

This hiss is audible even with both oscs on -
you can hear it in the background.  It blends
in with the sound.  
We checked all cables, connection, etc, no probs
there..  Nothing on the circuit boards appears
obviously blown.  All of the chips have been
firmly pressed into place.

WOOHOO!

I've swapped out the tlo82 & 3360 on the lower
& upper boards with known good chips.
The bleedthru problem remains.

Any idea what could be causing this?  It does
the same thing on upper & lower boards with
the lower board being more noticable.
Not specific to one particular oscillator.
also,
The bleedthru noise is louder in unison mode
on the lower voice board (voices 1-4)..
and is only heard whenever a key is pressed,
not constant.. hmmmm..