AirPlay 5.1 sound

I've noticed something odd...

When I AirPlay an album I've bought on iTunes (on my phone) to my Apple TV I get 5.1 sound. Looking at the track on the PC it is only stereo. (iTunes only synchronised stereo copies )

Is there something going on in the background? At first I thought it was 'fake 5.1' but it seems to good to be fake.

So is this real or fake 5.1? If real how do I get the 5.1 copies on my PC?

PS if I play a track that I did not buy through iTunes (copied off CD) then I do only get stereo ... nothing whatsoever out of centre and back r+l.

edit

Damn just realised that everything it playing in 'fake 5.1' ... it's because I forced the aTV to output PLII because it wan't auto selecting and failing to boot all the time.

Still it sounds better then just switching my AMP to 5 channel stereo

Edited by deleted (Wed 26-Dec-12 21:20:12)

Like you say in your edit. It's fake 5.1, it is very difficult to pull it off without introducing questionable artifacts. Some devices/software is better than others. I'm sure there will be an option to turn it off somewhere as a lot of audiophiles would not like such a feature.

As it's a track you've bought from the iTunes store, the phone will be playing a version downloaded (streamed?) from iCloud, not from your PC.

I think that if you delete the track from your PC then it will stay in the track list but with an iCloud icon by it¹- click that and it will download again, but whether it will be the 5.1 version I don't know.

(When you delete a track that's in iCloud, there's an extra checkbox asking if you also want to delete the iCloud copy. Don't tick it!)

Something similar happens with video content- I read up about that a few days ago but can't find the link I used and anyway it was about SD and HD video, not audio- have a Google around.


edit- I missed your edit . But what I said may still be valid...


¹ Assuming you've got "Show iTunes in the Cloud purchases" checked in Prefs => Store.

Edited by billford (Wed 26-Dec-12 21:33:07)

Hmm ... was actually a setting on the AMP.

aTV is just supplying stereo.

I had to mess about for ages to find a set-up that worked ok. Had to use HDMI direct to the TV with optic to the AMP otherwise the aTV wouldn't boot half the time (i.e. can't have HDMI into the AMP).

So how can I be sure I'm getting real 5.1 if I download a film?

edit

Ok figured that out too ... PLII changes to Dolby D on my AMP.

Edited by deleted (Wed 26-Dec-12 21:44:11)