Hi Tom:
The AP650 kit is limited to what comes in the box. It would not work to add a second or third speaker to the slave speaker. It would definitely throw off the internal receiver found in the master speaker. It is rated at 8 ohm powering a single pair of speakers with the internal drivers (woofer/Tweeter) being one and the speakers in the satellite being number 2. Adding a second speaker or pair would throw off the impedance and would create a demand for current while create to much heat for the internal amp. There is new technology available in some of the new smartphones that allows you to sync up with two Receivers so with this capability you could add another BTP650. You are not limited in the length of speaker wire other than you lose the true right and left stereo separation. We recommend between 8 to 12 feet. Additional wire maybe needed if you need extra wire to make sure it you get from Master to slave and are routing the wire around other objects there be no problem running longer than 12 plus feet. I was also going to say we are developing a Bluetooth outdoor Subwoofer (like the OSD OM SUB200) where we will have a Bluetooth Receiver built and a 4.1 Power Amplifier. You will have a powered outdoor sub with four conductors so you can connect two pair of outdoor speaker for better coverage. You can connect two pair of AP650 Patio Speakers (like the BTR-650 speakers) or two pair of Rock speakers or two pair of Omni or Garden Speakers, or mix and match maybe a pair of AP650 and a pair of RX640 rock speakers. W should have this in stock within the next 60 days or by the beginning of the second quarter 2018.
TL/ 4782