[sdiy] OT: Whole house audio

[Mike McCaughey]

Way off topic, but includes amps, VCAs and control voltages...

Anyone considered a DIY multizone home audio system?  Existing 
commercial devices run up to $2000USD for six zones of 12W audio and 
a good input switch matrix.  This should be possible for far, far 
less. A simple design:
  a six input/6 output line-level preamp that uses VCAs with external 
control voltages to control volume; a buffered 6x6 switch matrix pair 
(maybe an AVR to control using external signals for channel 
selection) and a dozen small amplifiers.

Anyone ever try or think about this?

On a related note, has anyone built a balanced line driver to put 
audio over Cat5 wire? Commercial devices exist, but is it as simple 
as building a few balanced drivers and putting the signal out on 
RJ-45 instead of XLR, or am I missing something?

Food for thought.

mrmike