6 to 8 channel audio player w/ amps for art installations?

[Michael Zacherl.]

Hi, 
how would you build a 6 to 8-channel audio player with amplifiers in the 100W rms/channel range?

I got some ideas but I'm afraid they are too complicated and expensive.
I'd like to get as many parts off the shelf as possible.

The set should be reliable and work unattended.
I had something in mind with a small linux-box, 5.1 S/PDIF output, and a digital amp with S/PDIF input, also to spare the conversion.
No idea if there are parts available to achieve something like that.

Any thoughts?

Thanks,  Michael.

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