surround sound with pc 5.1?



I've got a set of 5.1 cambridge soundworks home theater speakers or somethingl ike that, designed for pc use. now I believe these have some sort of amp - the sub takes 3x 3.5mm from the pc and then spits out 5 phono's to the FL, FR, RL, RR and C speakers. This also has a little wire to a volume knob, and it gets pretty damn loud - so I'd guess it has big amp in perhaps.

I'm looking into getting a JVC dvd recorder which has optical surround sound out. I have 2 questions:

1) is there a cheap device to turn optical 5.1 into 3x 3.5mm plugs
2) would these speakers work with something like that or would I need an amp?

both my Abit motherboards have onboard SPDIF and several jacks for surround speakers such as yours. I can select SPDIF as my input, and those speaker jacks as my output, so I would assume this would work, but I have never tried this.
ok yeah but is there a non-PC way of doing this? I should have made myself clearer, saying I've now got a new speaker system for my pc so I want to move this older, not-used set to the TV.
ah I see now, I don't have an answer then, but I am sure some others will know a solution.
Those are the only inputs? What model number is the set?

My Logitech Z-680s have optical and coax inputs for just this thing (one of the draw factors).

Does the JVC DVD recorder have analog (RCA) out? That may be the way to go... as you would be going from to digital to analog anyways (with the adapter that is).
the JVC has optical (I think its spdif) out for 5.1 but only phono's for left and right - AFAIK anyways.

the speakers just have C/B, RL/RR, FL/FR jacks on it. I could get the model number in a while...
As Treetop was saying, if your DVD recorder has analog 6ch output, then this would be your easiest option.
This is quite unlikely tho, as it would mean that there is an amp and a DD 5.1 ch decoder inside, but if you post the model number, I'd be happy to check the specs for you.

If not, I'm afraid there is no cheap option (at least not that I could find), because what you really want is an external 5.1 channel decoder (with at least DD 5.1 supported as this is the standard for DVDs), as you definitely have an amp in your sub, just no digital decoder.
These are v rare as most people use their amps for this. I only found one on the net, and it's not cheap, here is a link to a site where someone tested it:
Testing Ground: Technics SH-AC500D Decoder
Again, you may find a cheaper one as this one is very good and I'm sure your speakers do not need one of this quality, I just couldn't with a quick bit of Googling.

Your only other option is to buy a cheap 5.1 amp/receiver, but you need to MAKE SURE that it has 6 ch analog out (RCA cons) as many will only have speaker wire outs.
Maybe Ebay? ;)

Good luck!
If the DVD player can play DVD-Audio, then it probably has 5.1 analog outputs. Otherwise, it probably doesn't.
Good point smee, forgot about that!

Something to do with higher sampling rates not being supported by standard DD decoding amps, isn't it?