Originally Posted by mattlikesbikes
1. Sound creep from ceiling speakers. We don't want to piss off the upstairs tenant. Should I box in, or do some level of sound proofing directly behind speakers to keep the floors above from feeling or hearing too much? The house has the original oak floors and no real sound insulation between levels.
You should be concerned. I don't know if just boxing in the speakers will be enough. I'd be very careful here, contact Ted at The Soundproofing Company (here's here, mostly in the Theater Construction subforum) to discuss this with a real expert before doing anything.
2. Is 11' x 11' too small for a home theater room? Nothing crazy for the room, just our current 46" TV and either a 5.1 or 7.1 system (7.1 too much?). Just for netflix/movies/PS3.
Never too small... Doing 7.1 is usually an issue about speaker placement, not room size. If you can find locations for the 7.1 speakers, go for it.
3. For my mid room speakers (should I go 7.1) can I make them double duty? IE can I wire them into the TV room receiver and the whole house?
Yes, wire them like this: (diagram uses NuVo's term for the interrupt device)
4. Do you really need multiple speakers in rooms if the goal is just ambient music? I can cut my speaker budget in half by just going to one speaker in the bedroom, dining-room and kitchen. If I decide to add a second later, can I wire it in series with the existing speaker?
Do stereo speakers - if anything it allows better coverage at lower volume, so you get more even coverage in the room. If you do one speaker, adding another will be problematic, as placement for one speaker is very different than for a stereo pair. There are inexpensive speakers (Monoprice) - and it's easier to upgrade the speakers later if you choose than to try to undo a single-speaker arrangement. Swap is easy - adding requires drywall work/repair.
For bedrooms, think about placing in-ceiling speakers at proper "surround" locations (instead of centered in the room) if there's a TV planned. Then you can use the interrupt scheme (as above) later if desired. I wired all of my bedrooms in this manner just in case. It also places the in-ceiling speakers on either side of the headboard, so works well for music as well. Assuming the room has an obvious furniture arrangement. I forced the issue by placing wall-mount locations for the TVs.