Hi. I’m trying to connect 3 Zmacs in a row, based on the diagram in the Manual. The diagram only shows 2, but I’m using the connections shown there to expand to the third one.
I’m going from the Link Output on the second unit to the passive input on the third.
I’m going from the #1 “to speaker cab” output on the first unit to the #4 “from amp output” input on the third.
I’m able to listen to the amps on the first and second units on the cabs connected to the third unit.
The issue I’m having is a terrible noise when I try to listen to the cabs on the third unit.
If I use the active input on the 2nd unit (instead of the passive), I can get the 3rd unit to work, but then I have terrible noise on the second unit.
Has anyone gotten three units to work in series? Do I need some kind of transformer isolator somewhere in the chain to make this work?
It sounds like you may be getting a ground loop somewhere in the chain. Are you stacking these units? are they in a rack? are they being fed from the same power source? I have so many questions for you. Let’s just start with the ones I just asked, and we’ll keep it moving until this set up works.
Thanks for your reply. Sorry it took me a while but I wanted to take some time to try different combinations..
To summarize the setup, I’m running 8 different amps into the 3 Zmacs units.
All amps and the 3 units are being powered via the same Furman PL-Plus.
The amps are on a shelf and the units in a rack. Right now, there is 1 empty space between each unit.
All speaker and audio cables were soldered by me and have been retested to make sure they are working properly.
I understand that there are a lot of variables here, so I decided to simply the setup, and tried 4 amps into a single unit, removing the other two units from the rack.
Definitely some pretty bad ground. All amps exhibit ground problems to varying degrees.
The ground significantly reduced when I hit the ground switch on the Zmacs. The issue is the noise doesn’t completely go away (regardless of the amp I use). I have a few Radial Stagebug SB-6 (ISO boxes basically). When I connect them to the output of the Zmacs, the noise completely goes away, basically solving that issue.
As I add the second and third Zmacs units, all with Sb-6s on the outputs to the respective amps, I get a completely nose free setup. The issue that arises then is a terrible ground noise when I link the units using the Link output on the back.
A solution I guess could work is to NOT link the units and split the guitar with additional ISO boxes and then send them to each unit’s input (split BEFORE the Zmacs)… but this is all seeming overly complex. I can’t help but wonder if there is just something very basic that I’m doing wrong.
I’m going to try additional setups later today and will report back. Please let me know if you have any suggestions.
Hi Terry,
Hope all is well. Once again following up here. Can you provide any insight to things I could try? Does it make sense that I get a ground loop when I link the Zmacs together? Can you confirm if there is an ISO transformer on the link output?