Plugging TRS Cables into unbalanced jacks

[sada10]

I am going to start buying spools of cabling and begin making my own cables; the question that I have, is instead of getting a spool of both instrument and balanced instrument cables, I was just going to get balanced TRS cables and use them on my unbalanced instruments/processors/etc. Is this going to create grounding problems, hums, etc.?

[djui5]

yep......the connections aren't the same...

Why don't you solder ts connectors onto the end of trs cables?....just don't use one of the wires...make sure it's the same on the other end...use white and the sleve(ground).......

[penguin]

Or solder both the neg wire and ground shield to to the sleeve of the unbalanced connector. That is what is usually recommended when going from balanced to unbalanced sources.
Mark

[djui5]

Yeah......what Mark said.

[dpd]

Personal opinion - stay the heck away from cable with natural fiber fillers (like cotton wraps, threads between wires). They're just a mess when soldering.

I don't particularly like braided shields - you either cut them when stripping the outer jacket or they fracture when combing them out our while pulling the twisted pair or quads out from inside them. I prefer a 100% foil shield and a bare drain wire.

Go with Star-Quad cable - good for your balanced cables and still works fine for the unbalanced stuff, too. Mogami, Canare, etc. make this stuff. Gepco may, too.

Buy yourself a thing called a Solder Buddy (available at broadcast supply houses) to hold the connectors in place. Use a HOT iron (700+ deg) - get on, solder, get off quick - that way you heat the joint, melt the solder, but not the insulation.

And, don't scrimp on your connectors. Since you are making your own cables, you can buy connectors in bulk. I get great pricing from Gepco for connectors. Personal favorites are Neutrik XLRs but Whirlwind has some with colored boots that rock. I like Switchcraft TRS and TS - the all metal ones.

If I think of any more tips I'll try to post them here. Making cables saves $$$ but costs $$$ (your time)

[penguin]

Since Michael turned me on to Redco, I have retired my soldering iron. They make really high quality stuff, customized any way you like, really fast, for just a tad more than the materials would cost me to make my own... unless I buy 1000' rolls of wire of course.
Just a time saver tip...
Mark

[Ed Belknap]

Originally posted by dpd

I don't particularly like braided shields - you either cut them when stripping the outer jacket or they fracture when combing them out our while pulling the twisted pair or quads out from inside them. I prefer a 100% foil shield and a bare drain wire.

A fine idea for permanently-installed tie lines, but sheer suicide for any cables that are going to coiled & uncoiled regularly. Braided shield cables are infinitely more robust when subjected to repeated handling than any foil shield cables.

[DAS]

Originally posted by Ed Belknap
A fine idea for permanently-installed tie lines, but sheer suicide for any cables that are going to coiled & uncoiled regularly. Braided shield cables are infinitely more robust when subjected to repeated handling than any foil shield cables.

Absolutely!

Also, there is actually NO harm at all from using balanced TRS cables between two units with unbalanced connections. It will work just like a regular unbalanced cable. However, if ONE of the devices does have a balanced connection this type of cable may or may not cause some problems. But then so could standard unbalanced cables anyway. Any time you are connecting a balanced device to an unbalanced device you should check with the manufacturer(s) to make sure what they are doing on their I/O and what the best connect scheme would be.

[dpd]

Originally posted by Ed Belknap
A fine idea for permanently-installed tie lines, but sheer suicide for any cables that are going to coiled & uncoiled regularly. Braided shield cables are infinitely more robust when subjected to repeated handling than any foil shield cables.

Very good point, Ed. I guess I was thinking making cables for a studio that won't be moved much, if ever. You are right. I'd add for cables that will be moved around you want something that provides low handling noise. Unfortunately, this makes the cable somewhat less flexible. I think I've built some low-noise cables using some Mogami stuff back in the late 70's early 80's - and, they were reasonably flexible.

The good thing is that we rarely deal with very high impedances. Otherwise, cable construction for low noise is crucial.