If I read the question right, you are performing live to a BIAB backing track and, specifically, want the best possible sound from the backing track. Is that it?
Senior citizen's centers come in a variety shapes and sizes. You want a decent simulation of a professional sound system without lugging in a van load of equipment. I would start from there. You can play your tracks from any number of players or recorders. You want to be able to balance your work with the backing tracks and cover the range with loudness.
First thought, two 8 or 12"" powered speakers on stands, (Yamaha is industry standard, QSC is coming up fast on the rear, Guitar Center had Yamahas on sale @ $199 last week)) balanced with one of the recently popular four channel mixers (Mackie is one) and the player of your choice. My rig uses an eight track portable recorder (Tascam or Zoom) eliminating the need for a mixer. Your MacAir will work, too, especially if your music treats the DAW as another instrument, as a lot of looped for example or hip hop does.
Is that it?

Last edited by edshaw; 09/07/19 02:58 PM.
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