Need help with my first patchbay using balanced and unbalanced units

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

guilds100

Member
Joined
May 25, 2014
Messages
18
I need some tips on wiring my first patchbay. I have a patchbay that has hard wires already soldiered and I need to soldier trs, xlr or ts ends to the channel. The trs and xlr I can figure out, but ts is where I have my question. Do I just soldier the - and ground together on the ts connectors? Im using a focusrite liquid 56 and it will accept a trs or ts on the line in.
 
Look up the wiring for balanced to unbalanced connections. Experiment and see if your connection worked before making many of them. You could do it without even touching the patch bay.

Don't hot swap with tt or 1/4" cables while +48v is on. You will short the 48v to ground while connecting.
 
buildafriend said:
Look up the wiring for balanced to unbalanced connections. Experiment and see if your connection worked before making many of them. You could do it without even touching the patch bay.

Don't hot swap with tt or 1/4" cables while +48v is on. You will short the 48v to ground while connecting.

48V with 6k8 in series, no fire hazard with that.

For TRS or XLR I'd recommend to connect the shields at the patch bay end only and ensure the earth connection is solid for all the equipment, in order to prevent ground loops. You do need to connect the grounds of the Mic and preamps somehow, for the phantom, in that specific case you probably want insulated grounds in the patch bay which gets connected with the TT jumpers.

If you get to choose always choose balanced, so TRS over TS.

For the TS connectors you can't escape, connect the second wire (which would go to the ring) to the sleeve, and leave the shield unconnected, so if the device at the other end is properly balanced it works as it should, no ground loops. Then only if two such devices meet or an unprepared balanced one you get a problem, which you would have anyway. That's usually the best way for noises. Some devices just can't behave and you need to work on them to do it compatible with everything around or at least know with who they can interface without trouble.

Sometimes the device is almost always connected to the same location, let's say a delay which will always work in a send, maybe doesn't worth the headache to have it on the patch bay and in the case you really need to take it out, maybe twice in a year, you get behind the scenes and unplug it.

The thing is the patch bay usually creates a star ground which isn't optimal and brings the ground loops problems. The way to solve it is having the grounds isolated at the patch bay so each equipment handles itself but it usually comes with it's own problems. The best way of having everything working smoothly is the old EMI/Abbey Road's approach, each box inside your studio get's disassembled and reassembled with it's own standard (why 300Ω?). But that's too much for a personal/small studio, without a separate tech department.

JS
 
Thanks for the replies. I added a couple of pics for a more precise diagnosis. The green wire is connected to the shield grounds of the wiring. Im using one power conditioner to power the effects units. I will not be sending anything that has 48v on it through the patchbay,

 

Attachments

  • 100_0316.JPG
    100_0316.JPG
    171.6 KB · Views: 23

Latest posts

Back
Top