IMO you should give up on the idea of running a low-level signal all over the house. Use a speaker-level or even better a distribution system instead.
a) a low-level signal is much more susceptible to noise. You're running it over very long lines, otherwise known as antennae.
b) you'll probably end up with a very low effective input impedance, causing problems with the preamp and possibly introducing distortion.
c) room volume controls are a problem. They would have to be well shielded.
d) You will have to run both signal and power to the speakers. That is a serious problem for a whole-house system since the speakers are set into the wall or ceiling.
Consider a 70 volt distribution system.
a) a low-level signal is much more susceptible to noise. You're running it over very long lines, otherwise known as antennae.
b) you'll probably end up with a very low effective input impedance, causing problems with the preamp and possibly introducing distortion.
c) room volume controls are a problem. They would have to be well shielded.
d) You will have to run both signal and power to the speakers. That is a serious problem for a whole-house system since the speakers are set into the wall or ceiling.
Consider a 70 volt distribution system.
