pbdelete wrote ...
I'm curios wheather useing a corrugated catv distribution cable like
these:
http://www.outokumpu.com/files/Coppe...M_coaxial2.jpg
(diameter often 2 cm ~1 inch)

Could be benefitial to wire speakers with? Point being shielding from
external
sources. And esp keeping the high frequencies (10-20kHz) in the cable.
The size of the cable should sufficient for the load.

Just an wild idea

Too wild. No advantages. Many disadvantages, several
of which are deal-killers IMHO. You don't need shielded
cable for speaker-level. (Unless you have a 50KW transmitter
on your roof.) That stuff is way too stiff and difficult to deal
with to make it worth considering except for its intended
purpose (where it is better than its predecessor, hard wave-
guide.)