I’ve never known TS vs TRS to matter, except for eliminating hum. So I’d guess something else is going on. But I don’t know what 🤷‍♂️

 

The output is line level. Are you plugged into a mic-level input or a line-level input? Most mixer inputs will be mic-level. There are usually special ones labelled line-level (or there will be a switch on the channel to switch between mic/line levels).

 

I run into a u16 sound craft and go into a mic level input, I think. From my understanding, that’s why the xlr/TRS cable from the back of the tonemaster works?

 

An alternative is to send one output from your UA Lion to the FR12, and the other one to the Soundcraft (one of the high-z instrument level inputs). Or, take a lead from the UA Lion into a DI Box, then to the board.

 

DI into a mixer usually sounds like shitake.
For some reason nobody has ever made a DI that sounds good...
It works for cleans but not for much else.

Crank the amp up, Mic the speaker cabinet, use an attenuator (one of several types) to get the stage loudness under control.
The result will sound much better.