> Through trial and error I've learned that most multimedia units from
> the 70s will have a quad 8 track deck but only normal 2-channel,
> stereo phono.

Hmm, I assume by "multimedia" units, you mean those quad am/fm/tape/phono
combo recievers. A lot of those have a crude decoder in them for one of
the matrixed quad systems, a few don't. I'm not aware of any that
actually have a good quad decoder/demodulator built in.

Any tips on where I might find an actual quad LP player
> with the proper stylus, etc. etc.? I've been watching eBay and haven't
> seen much at all.

What format do you want to play? For CD-4 (Quadradisc) you need a special
setup, but otherwise any standard player will work. I've been told that
for CD-4 you're best to go with a direct drive turntable, better yet a
linear contact (I think that's what they're called, with the tone arm
always 90 degrees to the record). Good brands to go with are those who
origionally supported the format, JVC, etc. A shibata (also called line
contact) stylus I believe. Hope that helps!

Dan