Doepfer

Thanks, the cables are all recent doepfer
Not sure to know how to do this experiment though I will try. 
Which GND do you refer to? 
Just the one of the audio 2 (the source which feeds the A138s) or the multed audio 1 as well?
Audio 2 is from a DPO mounted on a A-100P9 PSU3
Audio 1 is from a Bastl Instruments SoftPop, which in the meanwhile went back to the dealer to be replaced for another kind of issue. I had noticed some electricity at fingers while touching the side panels of its case. It probably is not properly grounded, though it shows some sockets for grounding.

Best wishes,
Diego


> Il giorno 12 giu 2018, alle ore 14:54, yahoo@doepfer.de [Doepfer_a100] <Doepfer_a100@yahoogroups.com> ha scritto:
> 
> As external audio signals are involved it maybe a grounding problem. Make
> sure that the cables that are used to connect the modules to the external
> signals carry GND (there are patch cables available without GND, as long as
> one patches within the case no problems occur, but with external signals the
> GND is missing). And I don't know if all WMD sockets are grounded. In some
> modules (yes, also in some older A-100 modules :-) the GND of some sockets
> is not connected as it does not matter if all modules are connected to the
> same GND.
> You may try also the following: connect the GND of the A-100LC3 temporarily
> to the GND of the signal source unit (at the A-100LC3 there should be an
> unused GND terminal on the bus board). If then the problem disappears it's a
> grounding issue.
> It's just an idea. Not sure if this is the reason.
> 
> Best wishes
> Dieter Doepfer
> 
> 
>> -----Ursprüngliche Nachricht-----
>> Von: Doepfer_a100@yahoogroups.com [mailto:Doepfer_a100@yahoogroups.com]
>> Gesendet: Dienstag, 12. Juni 2018 14:06
>> An: Doepfer_a100@yahoogroups.com
>> Betreff: Re: [Doepfer_a100] Interferences from A-138s into LC6
>> 
>> 
>> 
>> 
>> Hi thanks everybody for replying
>> The situation was vague indeed, sorry, though the patch is very basic
>> The case is just 1 row (LC3)
>> As you can see by the colours on the following screenshot, the
>> multed audio 1 signal (red cable) is slightly affected by the
>> audio 2 signal (blue cable), as we turn CW the A-138s channel volume knob.
>> 
>> 
>> Nothing else is patched/ engaged.
>> 
>> 
>> I unfortunately have no means nor expertise for measuring anything.
>> ASAP I will first try installing the multiple on another case.
>> 
>> 
>> Best, Diego
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> Il giorno 12 giu 2018, alle ore 10:25, John Hollis
>> john@hollis.co.uk [Doepfer_a100] <Doepfer_a100@yahoogroups.com>
>> ha scritto:
>> 
>> 
>> Hi Diego,
>> 
>> It does sound like there might be a short between the adjacent
>> modules. Can you check for that?
>> 
>> Thanks
>> John
>> 
>>> On 12 Jun 2018, at 08:57, yahoo@doepfer.de [Doepfer_a100]
>> <Doepfer_a100@yahoogroups.com> wrote:
>>> 
>>> Hello,
>>> 
>>> the A-138s is a very simple module (just a standard mixer circuit with
>>> operational amplifiers) and I have no idea how the signal could
>> crosstalk to
>>> any other module.
>>> 
>>> Best wishes
>>> Dieter Doepfer
>>> 
>>>> -----Ursprungliche Nachricht-----
>>>> Von: Doepfer_a100@yahoogroups.com
> [mailto:Doepfer_a100@yahoogroups.com]
>>> Gesendet: Montag, 11. Juni 2018 15:09
>>> An: Doepfer_a100@yahoogroups.com
>>> Betreff: [Doepfer_a100] Interferences from A-138s into LC6
>>> 
>>> 
>>> Hello, I have a WMD buffered multiple which suffers from A-138s
>>> mixer interferences, both powered by an LC6 Doepfer case. Is the
>>> WMD faulty or its cable? A-138s output can be heard on the WMD,
>>> unless knob's fully CCW. I also see that the multed signal is
>>> louder that the original one. Any hint is welcome.
>>> 
>>> Best regards,
>>> Diego
>> 
>> 
>> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> ------------------------------------
> 
> ------------------------------------
> 
> 
> ------------------------------------
> 
> Yahoo Groups Links
> 
> 
>