From yahoo Sent Wed, Jun 13th 2018, 07:54
From yahoo Sent Wed, Jun 13th 2018, 07:54
It's not for sure that this is the reason for your problems. So I'd recommend just to try it out, i.e. connect the GND of the A-100LC3 temporarily (e.g. the GND blade terminal on the A-100 bus board) to GND of the other devices included in the signal path. If you use an A-100LC6 (mentioned in the subject of your message) that not necessary as the A-100LC6 GND is connected to mains earth/GND. Does the problem also occur if you use the A-138s outputs directly (without the buffered multiple)? Best wishes Dieter Doepfer > -----Ursprüngliche Nachricht----- > Von: xxxxxxx_xxxx@xxxxxxxxxxx.xxx [mailto:xxxxxxx_xxxx@xxxxxxxxxxx.xxx] > Gesendet: Dienstag, 12. Juni 2018 19:43 > An: xxxxxxx_xxxx@xxxxxxxxxxx.xxx > Betreff: Re: [Doepfer_a100] Interferences from A-138s into LC6 > > > Ok thanks, so I have to learn how to ground it ! > It seems obvious but not > I will try > > Floating GND (?) needs to be deepened > Or I’d better search for someone who can do it? > > > > Il giorno 12 giu 2018, alle ore 15:57, xxxxx@xxxxxxx.xx > [Doepfer_a100] <xxxxxxx_xxxx@xxxxxxxxxxx.xxx> ha scritto: > > > > I fully agree. As the A-100LC3 also uses an external power > supply it's GND > > is not connected to mains earth/GND and has the mentioned > "floating GND" (in > > contrast to all other A-100 cases). > > > > Best wishes > > Dieter Doepfer > > > >> Definitely get that case properly earthed first. Even if its not > >> causing this issue, its not safe for you or your equipment. There > >> should be a both crimped and soldered lug on the metal case, held > >> in good contact with a screw and washers which connects to earth. > >> This probably can be done by connecting the PSU ground to the > >> case, but its worth checking that the case actually is > >> electrically connected to the ground pin on your wall socket. > >> Some PSUs with external bricks have a floating ground > >> > >> > >> On 12 Jun 2018, at 14:20, Diego Ragnini xxxxxxx@xxxx.xx > >> [Doepfer_a100] <xxxxxxx_xxxx@xxxxxxxxxxx..xxx> wrote: > >> > >> > >> > >> 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, xxxxx@xxxxxxx.xx > >> [Doepfer_a100] <xxxxxxx_xxxx@xxxxxxxxxxx.xxx> 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: xxxxxxx_xxxx@xxxxxxxxxxx.xxx > >> [mailto:xxxxxxx_xxxx@xxxxxxxxxxx..xxx] > >>>> Gesendet: Dienstag, 12. Juni 2018 14:06 > >>>> An: xxxxxxx_xxxx@xxxxxxxxxxx.xxx > >>>> 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 > >>>> xxxx@xxxxxx.xx.xx [Doepfer_a100] <xxxxxxx_xxxx@xxxxxxxxxxx.xxx> > >>>> 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, xxxxx@xxxxxxx.xx [Doepfer_a100] > >>>> <xxxxxxx_xxxx@xxxxxxxxxxx.xxx> 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: xxxxxxx_xxxx@xxxxxxxxxxx.xxx > >>> [mailto:xxxxxxx_xxxx@xxxxxxxxxxx.xxx] > >>>>> Gesendet: Montag, 11. Juni 2018 15:09 > >>>>> An: xxxxxxx_xxxx@xxxxxxxxxxx.xxx > >>>>> 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 > >>> > >>> > >>> > >> > >> > >> > >> > >> > >> > > > > > > > > ------------------------------------ > > > > ------------------------------------ > > > > > > ------------------------------------ > > > > Yahoo Groups Links > > > > > > > > > > ------------------------------------ > Posted by: Diego Ragnini <xxxxxxx@xxxx.xx> > ------------------------------------ > > > ------------------------------------ > > Yahoo Groups Links > > > ------------------------------------ ------------------------------------ ------------------------------------ Yahoo Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Doepfer_a100/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Doepfer_a100/join (Yahoo! 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