You may also want to check out Partsexpress.com and look at their impedence matching volume controls. With these you can use any 2 channel amp or receiver to run all your in wall speakers. They sell a distribution plate that will allow you to use up to 10 pairs of speakers. Good luck.
Advice for amp with in wall speakers.
In addition to my main system, I want to have a second system that plays throughout the house and outside. I would like advice on a second power amp that would drive six or eight speakers. My understanding is that this causes an impedence problem. Is this correct? What do I need to look for in an amp? I plan on using the preamp from my main system, directed into a box that will switch the in wall speakers. How much power do I need, and do I need an amp that will go below 4 ohms. Thanks in advance for any help.