Using TV as Audio Hub?


OK - That title probably makes no sense. Here's the situation. In our guest room/playroom/gameroom, we have a 37" LG LED TV, with the following sources: DirecTV receiver, Sony BDP, Apple TV and Wii. I want to hook up a pair of PSB bookshelf speakers I have lying around for a simple 2-channel system.

I want to get a simple receiver or all-in-one type unit to run the sound to the speakers.

Since all of the sources are already hooked up to the TV set, and the TV has an optical output for audio, I could just run a Toslink cable from the TV to a DAC and small integrated amp (or a combo DAC/Integrated), and let the TV handle the source switching.

If I do this, will the sound quality be materially worse than if I ran all of the sources directly to the receiver for audio?

I was considering getting something like the Wadia 151 PowerDAC ($800) or an NAD VISO TWO ($500).

Thoughts? Simple is best.
mateored
For the life of me I don't know why everyone has to make things so difficult.The system you have in mind will work perfectly so just stick to your original plan & run an Toslink from the tv to a nice little all in 1 like the Wadia or a Peachtree Audio & enjoy.
I have a Peachtree Audio MusicBox with Sonus Faber Toy Monitors for PC based audio,I also run a Wireworld Glass F/O Cable from TV to the MusicBox for video & it sounds AWESOME!
This is exactly what I do in my family room with DirectTV, APpleTV, and Blu Ray running to TV , then out to a Bel Canto Integrated w/ DAC via TOSLINK. Works pretty damned well. I am pretty sure my DAC is reclocking the bits and bytes so unless there is loss somewhere in the path, it should be identical to direct from source.
I'm doing the same. HDMI from all sources into the TV and digital out into Wadia. Indistinguishable from CDP direct digital, or laptop USB into said Wadia. The convenience and simplicity cannot be beat - especially with nothing lost in translation (the TV does only pass-through, no resampling as best as i can tell). YMMV.