Doepfer

Hi Peter,
 I don't have an A116, but if it is anything like the A-136 then this
sounds terribly like the ghost of '150 bleed-thru revisited',
discussed at length some weeks back. My guess would be that if the 116
*is* like the 136 and has the capability of amplifying the input
signal greatly, then the signal into the 150 may be more than +/- 8V,
which we know it is very unhappy with! If you have a scope and can
check out the size of the signal you are passing into the 150 (do it
*without* the connecion to the 150 being made, as otherwise the diodes
in it will make it seem like about +/- 8.7 V, whereas in fact it could
be higher) then I would be most interested to hear if this is the case
or not. I still don't appreciate why the FET circuitry in the 4053
chip behaves as it does under such conditions, but I shall continue to
seek an answer - today I printed yet another 4053 datasheet, unlike
the others I have this one shows the exact configuration of
transistors in the switch, so I may yet be able to work it out!

Tim

[The views expressed above are entirely those of the writer and do not
represent the views, policy or understanding of any other person or
official body.]


> Connect a sine into the A-116.  VC the shift with a ramp LFO.  
> Listen to it.  You will hear a tiny bit of waveshape modulation, 
> nothing to go bats over.
> 
> Take the output of the A-116 and route it into the INACTIVE I/0 
> jack of the VC switch (the one in which the LED is OFF).  do not 
> connect a VC into the switch, let it stay in that state.  Listen to the 
> output of the VC switch.
> 
> You will hear an incredible amplification of the waveshaping 
> effect now.  I have no idea why this is happening.  If there is no 
> VC into the switch in order to connect the output (wiper) to the 
> normally open contact (the I/0 without the LED on), then you 
> shouldn't hear a damn thing....but you do.  I tried it on both the 
> upper and lower VC swtch, worked like a charm.
> 
> try it,m you might like it.
> 
> best,
> 
> Peter Grenader