On 2007-01-21, 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?

a couple of 1K resistors will be enough to protect your soundcard's outputs
from each other.

.-------------------------------------------------------------.
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`-------------------------------------------------------------'

fixed channel combiner
.----- right left
Sterio jack plug | | | / |\ /|
_ _ ____ ___________| | | / | \/ |
/ ~-_/ ## | ## | | / | / |
/ `-----------------------| / |/ |
\ _-------------------------------/ common | |
\_-~ \_##____##___________-----------------------------------
| |
| |
`-----'
common 1 ---.
|-------------- common out
common 2 ---'

left 1 --[1K]--.
|----------- left out
left 2 --[1K]--'

right 1 --[1K]--.
|---------- right out
right 2 --[1K]--'

If you get hum from that something more elaborate is needed

I've not seen cables like this for sale anywhere so you'd have to make
them. the cheapest way to do a reasonable job is probably to solder
the resistors in-line and use heatshrink to insulate and strain-relieve
the joint

--

Bye.
Jasen