These type of installed systems are fundamentally different than music PA systems. On many of the systems, each individual speaker has an amplifier that is built in that draws power from the DC signal passed from the distro amp. The distro amp supplies both the music as well as DC power on just 2 wires. It's a different situation than trying to drive 20 speakers with the AC music signal from an amp.

We normally don't deal with that here in this forum. I would suggest your friend find a local NSCA qualified business (National System Contractors Association) that can come in and assess the situation and suggest some equipment. This should be a no-brainer for one of these guys. Member Directory is here: http://www.nsca.org/Home/IndustryResources/MembersontheMap/tabid/360/Default.aspx

My skeptic's eye is trained on the 'Both amps went this week' comment, as being possibly indicative of some design or wiring situation that loaded the 2nd amp improperly when the first amp died - but that's just the internal Sherlock Holmes wanting to have some fun.

-Scott