(In this case when I say TRS I mean 1/4in instrument cable)

I've got a Behringer 4-output headphone amp that has inputs for either 2 mono 1/4in cables or 1 stereo 1/4in. The output on my particular choice of interfaces (being PreSonus thus far) is always ONLY a pair of mono 1/4in outs (L/R of course), but I'd like to reduce my amount of "cablelage" (making up words 101) and avoid having to purchase 2 25ft TRS cables.

Would a 2-male TRS-to-female TRS connected to a stereo TRS cable plugged into the stereo input on the HP amp be adequate for this? I've never used stereo TRS cables so I'm curious as to whether this is a standard method, or are there actually any better options even?

Am I understanding you correctly, and the L and R outputs on the interface use TRS cables? If so they’ll be a “balanced” circuit which, to cut a long story short, uses a 2-core and braid cable in such a way that noise induced in the cables is massively reduced.

However, most such jack circuits will also accept a “mono” TS jack, but you lose the advantage of the noise reduction (and sometimes the output or input level is reduced as well depending on how the circuit’s designed).

By the sounds of it the Behringer accepts only an unbalanced signal, either two TS cables or a single stereo jack.

OK. One option is to get (or make if you have basic soldering ability) an adaptor that has two male TS jacks run by short wires into a single female TRS socket. Plug the male jacks on the adaptor into the Presonus then run a TRS cable from that to the Behringer.

This is the sort of thing I mean - https://www.gear4music.co...FxW3uthpxoCOsIQAvD_BwE

Just run ONE TRS (=Tip/Ring/Sleeve=Stereo 1/4 ") cable from the headphone output of the interface to the 1/4 " stereo in of the headphone box!
 
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