Obviously, you'd be fine if plugged into 120 volt shore power.
If you run it off an inverter, be prepared to chew through your battery / batteries in a real hurry. With the inverter, going from 12 VDC to 120 VAC is pretty inefficient, and with the TH-F3 dissipating 90 watts you'll be dropping the battery / batteries down into a severely discharged state quickly. I base this on my experience with a VPAP machine. After 6 hours or so on the inverter, it had drawn my 2 x 6 volt batteries down to 40%, and I suspect that the VPAP was drawing a whole lot less current than the amplifier in your JVC. Running it off of a 12 VDC -> 24 VDC converter (the VPAP needs 24 VDC), the VPAP only runs the batteries down to 75% overnight.
But you would sure have a real nice sounding trailer while it lasted!
Discretion is the better part of boredom.
Tow Vehicle: 2012 Toyota 4Runner Trail, KDSS, BFG A/T KO's, ScanGauge, B&M Tranny Cooler, 20" Opt7 LED Light Bar, LED DRL's, Prodigy P2 Controller, Timbren Rear Springs