You probably can, I pulled them out of a shop install so figured I would just re utilize them
They are not designed for home use but for retail space where multiple speakers are needed. They have mediocre frequency response and require active equalization (without equalization they will sound horrible). If you want music to sound like it does in a dentist's office or clothing store, go ahead
. Because of the number of speakers these systems are designed to work with, they typically need specialized amps or wiring (the manual specifically mentions the use of a multi-tap transformer). They are rated at only 4 ohms per speaker with no transformer, so connecting 2 speakers in parallel could potentially damage an amplifier if just running in stereo.
For separate volume in different rooms, the cheapest option is an audio video receiver with a "Zone 2" option. Some home theatre receivers can take 1 channel from the surround amps and redirect it to a separate room independent of the main and surround speakers. So if you had a home theatre receiver that supported 9 speakers, you could set the receiver to use only 7 speakers and run the other two in second zone. Beyond two zones I would recommend contacting a professional.