I remember paying a visit to the Classic FM studio in London to do an interview in the 1990s. I was very surprised (at the time) to see ordinary two core (and earth) mains cable wiring up the studio monitors. (NB. the earth was left folded out of use). I guess they knew something better than the guys who need to make a living selling cables!

Roy Woods
Sony BDP-S370, G98DH, G68D, (FS: 562V), DSP5000C, DSP5000, M60, Pioneer PDP507