Currently I have a 70 volt system that I'm considering changing and I have a quick question I need answered. The system consists of 10 speakers total - 1 in the main sanctuary, and 9 throughout the rest of the building. This is driven by a Peavey PV900 amp in bridge mode (600 W RMS @8 Ohms). My goal is to send a different mix to the sanctuary speaker than is going out to the other rooms (I'd like to mic the congregation and choir for this mix and don't really want it in the sanctuary). So my question is can I take the amp out of bridge mode and drive the sanctuary speaker on one channel and the other rooms on the other channel? Since the amp is no longer in bridge mode, I suspect I'd need a couple of step up transformers. If all of the speakers are using the 10 watt tap can I get by with a 200 watt transformer? At 8 Ohms, this amp is rated at 180 watts per channel so it appears that 90 total watts (9 speakers) with the 200 watt transformer should work.
I'm an IT guy by day so I'm pretty comfortable with technical things, but I'm a little shaky on the specifics of 70 volt distribution. My research so far suggests what I've proposed above, I'm just looking for a little expert opinion! Hopefully I'm not too far off!