Surround Sound

I currently have my tv cable box audio going thru my stereo amplifier on channel A in order to listen to the multiple music channels available on my cable. Hoping to get an inexpensive method to provide surround sound for movies etc while watching tv, I was planning on connecting computer 5.1 surround speakers to channel B. I know this will work especially if I use the Logitech X540 with the matrix option to enable the rear speaker even with only 2 channels. My concern is the output from the stereo might be too high for the computer speakers to handle. Although the computer speakers will generate up to 140 watts, their input is expecting a low signal from a computer audio card.

Does any one know:
1. What is the output wattage for a computer audio card?
2. What is the max input wattage for computer speakers?
3. What is the input wattage to a non-computer surround sound system? I'm guessing fairly low as well.

Any other comments will be appreciated.

Thanks

G

 

I found the info...

Here it is for others:

>1. What is the output wattage for a computer audio card?
around 400mV

>2. What is the max input wattage for computer speakers?
May are rated as 250 to 400 mV - but I can't find the max value

>3. What is the input wattage to a non-computer surround sound system?
Many are rated between 250 and 400 mV for input sensitivity

Bottom line, if you do this like I have, it works great but you better remember to turn your stereo volume off before turning on your computer speakers otherwise you will fry the 5.1 computer amp. Your best bet is to turn off both volume controls, then turn up the computer speakers to 3/4 and then inch up the stereo volume to a reasonable level.

Cheers