\rHi Rick:
Unlike the Wireless versions which can have both pair of speakers be driven by a single transmitter the BTR speakers can only sync up with a single pair at a time unless you have one of the newer smartphones which sync up to two receivers at once. What you might consider is purchasing our new BOM4.1 which features our OM SUB 200 8.0" Outdoor Powered sub woofer with an internal 4.1 amplifier with four powered output wires so you can drive 2 pair of speakers. You could use the 2 satellite speakers from your current WR-150 rock speakers (the ones connected to each of the master rock speakers by speaker wire). I am assuming the receiver is no longer working in one of your master rock speaker but the satellite should still be good.You can purchase a pair of RX150 rock speakers and connect them as the second pair. This would give you the two pair plus a complimentary sub woofer for better fill for your back yard. That would give you your two pair matching the WR150 plus adding an 8.0" sub.
Let me know if you need further clarification. tim@osdaudio.com
TL/4974\r