Could a DAC produce noticeable improvements to my AV system?

[KidKomet]

Evening all!

I have an Onkyo 616 powering my Q Acoustics 7000's. I play games/watch Blu rays through my PS3 and occasionally watch a little TV through the Sky+ HD box. My question is, would including a DAC (Such as the new Arcam IrDAC) in the mix yield worthy results, do you think? My knowledge in this field is still rather limited at the moment so my apologies if this all seems a touch moronic.

I was looking at maybe £350. Sadly I don't know anyone who has a DAC I can borrow to test.

 

[The_Lhc]

All of those sources are multi-channel devices, the Arcam is a stereo device, it won't be any use for those things.

 

[The_Lhc]

Ffs!

 

[KidKomet]

Probably a good job I didn't buy one then ha! Thanks for the help. Maybe I should just suck it up and start saving for a new rig. The sound isn't exciting me as much as it used to.