"paddy" wrote in message
...
If I want to be able to send the signal from a CD player (or record
deck) to

a) amp (for "pure" listening)

- OR -

b) rough old DJ mixer (for occasional parties)

... is it an acceptable option to use a "Y" splitter cable out of the
CD player (record player)?

I want to avoid doing any replugging when moving from "audiophile
mode" to "party mode". When in "audiophile mode" the mixer would be
turned off. I have tried to look around for an answer to this, and
while people seem to react against Y splitters, I haven't been told
exactly WHY they are such a bad idea.

Is there a good electronics engineering reason to avoid them? Would it
make any detectable difference in the real world (double-blind testing
etc etc)?

Frankly, I've used "Y" splitters many times both in and out, and have never
had a problem. I try to make sure that I have only one piece of the "Y"
active at any time, as your say you do. Theoretically, I suppose you could
have an impedance problem if both pieces of gear receiving the signal had
marginally low input impedances, but I've never experienced that in the real
world.