Hello, regarding the floating GND matter, has the Ribbon R2M control box a floating ground as well? In other terms, do I have to connect the black box metal frame to the ground/earth? Best, Diego > Il giorno 20 giu 2018, alle ore 09:58, yahoo@doepfer.de [Doepfer_a100] <Doepfer_a100@yahoogroups.com> ha scritto: > > Yes, these are the correct terminals. If the GND connection really solves > the problems one has to think about a permanent solution. But I have never > heard about similar problems from other customers. And we use A-100P9 > together with A-100LC3 during exhibitions or work shops and never had any > problems. > > Best wishes > Dieter Doepfer > > >> Please can someone check that this would be the right connection >> in order to grant that the A-100LC3 “GND” is temporarily >> connected to mains earth/GND? So I would temporarily connect the >> blade terminal of the first picture to the same blade terminal >> found in the A-100P9 (2nd picture).. Then, in order to set a >> definitive connection, I would provide a mains “plug" where to >> pass uniquely cables for all floating GND's in the system towards >> the mains earth/GND pin wall socket. Would both these solutions >> be correct, please? >> Best, Diego >> >> >> >> >> >> >> >> >> >> >> Il giorno 13 giu 2018, alle ore 09:53, yahoo@doepfer.de >> [Doepfer_a100] <Doepfer_a100@yahoogroups.com> ha scritto: >> >> >> 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: Doepfer_a100@yahoogroups.com [mailto:Doepfer_a100@yahoogroups.com] >> Gesendet: Dienstag, 12. Juni 2018 19:43 >> An: Doepfer_a100@yahoogroups.com >> 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, yahoo@doepfer.de >> >> [Doepfer_a100] <Doepfer_a100@yahoogroups.com> 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 diegora@free.fr >> [Doepfer_a100] <Doepfer_a100@yahoogroups..com> 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, 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 >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> ------------------------------------ >> >> ------------------------------------ >> >> >> ------------------------------------ >> >> Yahoo Groups Links >> >> >> >> >> >> >> >> ------------------------------------ >> Posted by: Diego Ragnini <diegora@free.fr> >> ------------------------------------ >> >> >> ------------------------------------ >> >> Yahoo Groups Links >> >> >> >> >> >> >> >> ------------------------------------ >> >> ------------------------------------ >> >> >> ------------------------------------ >> >> Yahoo Groups Links >> >> >> >> >> >> >> >> >> >> > > > > ------------------------------------ > > ------------------------------------ > > > ------------------------------------ > > Yahoo Groups Links > > >
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Re: [Doepfer_a100] Interferences from A-138s into LC6
2018-06-28 by Diego Ragnini