What is an inexpensive ac3/dts decoder?

[Stealth3si]

I have no way to pass the digital signal from my WDTV Live to my 5.1 speaker system setup because they're hooked up to my Audigy 2 that doesn't accept 5.1 input or decode AC3 or DTS!

I am looking for a "AC3/DTS 5.1 decoder" that is able to accomplish the following tasks:

Inputs:
1.) multi-channel analog input (3x3.5mm OR 6 RCA)
-OR-
2.) digital input (optical) that accepts multi-channel source


Outputs:
3.) multi-channel analog output (3x3.5mm OR 6 RCA)
4.) headphone jack (3.5mm or 6.35mm)


The "AC3/DTS 5.1 decoder" in question could either be a:

1.) PC sound card
-OR-
2.) Audio Amplifier/Receiver
-OR-
4.) Something like the Creative DDTS-100 (http://au.creative.com/products/product.asp?category=4&subcategory=136&product=9468)

I prefer something that is "bang for the buck."

Please recommend me specific items.

TIA.

[Blue_MiSfit]

To clarify, here's what I'm getting from your post

1) WDTV Live can output S/PDIF over an optical TOSLINK connector
2) Your speakers are of the "multimedia" variety - meaning they have built-in amplifiers, and only take line level signals from 3x 3.5mm jacks or 6x RCA jacks. Mine are the same (Klipsch ProMedia 5.1)
3) Your speakers are currently plugged into the 3x 3.5mm jacks on your Audigy 2
5) Unfortunately your Audigy doesn't have a S/PDIF optical input

OK, so you need to go from optical S/PDIF to 6ch line level analog. This basically rules out the easiest solution - a cheap used A/V receiver - because such receivers usually only have high level outputs (i.e. speaker connections, not 3.5mm @ line level).

Here's a fairly simple option: Replace the Audigy 2 with something like this (http://www.auzentech.com/site/products/x-raider.php), that does have the TOSLINK input. Worst case you rig up a little DirectShow filter graph that takes input via the TOSLINK conector input, and feeds it into ffdshow for decoding into PCM.

Another solution is to replace your speakers. I don't know what the model of your speaker system is, but if there's a central subwoofer / amplifier like with mine, you may be able to re-use the actual speakers themselves with a new A/V receiver. Then you loose the subwoofer though...

Tricky question... If your WDTV live is near enough to your computer to actually connect the two, why use the WDTV live at all? Just curious..

Derek

[TinTime]

I'd look out for a used AV amp / receiver. Plenty of them will have RCA pre out sockets on them and you should be able to get an old one for very little money.

[SeeMoreDigital]

Creative make an SPDIF I/O module for their audio cards... or at least they used too.

I bought one for my Audigy sound card...