Noozer wrote:
I want to combine the line output from to PC's into a single set of
speakers. I know that reversing a Y cable is probably a bad idea. What's
the simplest way to do this properly?

Let's see.. you have two PC line outputs (normally these are stereo, so
2x Left and 2x Right) and you want to have one set of (must be)
amplified speakers for both computers. Okay, you need two stereo 3.5mm
(1/8th inch) plugs to match the soundcard outputs, and four resistors of
about 4.7 kilohm (or anywhere between 2k and 10k, so long as they are
all the same), plus one stereo 3.5mm socket (or whatever your amplified
speakers need to plug into), plus some cable. You might be able to get
all of this other than the resistors already made up in a Y cable like
you suggested then snip it in two places, in the line of each of the two
cables going from the 3-way join to the plugs that go into the PCs
probably if your Y cable looks like I imagine it.

The important thing is to put a resistor in series with each line output
(two lines, each with L & R outputs means 4 resistors), with the other
ends of the resistors joining to go to the single line (L or R) to the
amplified speakers. If they aren't amplified speakers you won't get any
sound, by the way. If it is a single (mono) amplified speaker you can
mix them all down into one channel instead of Left & Right. If you need
more help let me know (I didn't try drawing a circuit 'cause I don't
think ASCII artworks are going to make it clear enough).

Mark A.