Hi,

You would have to use some variation on an FM modulator, which would be a small low-powered FM transmitter plugged into the headphone output of your indoor Yamaha. Then you'd need the FM receiver at the other end, plus an amplifier to drive the speakers.

In the end, that seems more complicated than just running some speaker cables out to the speakers.

Regards,

Alan Lofft,
Axiom Resident Expert (Retired)