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stoid
Jul 4, 2004, 11:54 PM
Airport Express has the optical audio port. Does this mean that it can support 5.1 surround sound? If so, wouldn't it make sense for iTunes to start supporting DVD Audio or for the DVD player or different games and the like to also begin to support the Airport Express wireless connectivity?

I think that the biggest thing in your living room may get bigger very easily and quickly!

ChrisFromCanada
Jul 5, 2004, 12:26 AM
Although you prediction could be right. Optical audio supports 2.1 also (and I quite sure that is all airport express will ever support). The point to the optical audio is to keep the signal digital as long as possible.

Also I'm not too sure where you are going with this. You can listen to a DVD in 5.1 while watching it on you computer? It dosen't add up.

stoid
Jul 5, 2004, 12:29 AM
Maybe not DVD player, but I know that console games can support 5.1 surround, so why not computer games. Also, DVD Audio is recorded in 5.1 surround in 24-bit rather than 2 channel 16-bit CD quality audio. I've you've never heard DVD Audio, then you are missing out, it sounds amazing!

JFreak
Jul 5, 2004, 01:03 AM
yes, 24bit audio is a huge step forward compared to 16bit audio. those missing bits have been THE reason for the neverending vinyl-sounds-better-than-cd discussions ;) now that digital audio has 24 bits, the available dynamics exceeds the dynamics our ears can hear - +140dB anyone? regular ear hurts at 120dB.

of course, the multi-channel audio would also be nice. but even 24bit stereo sounds great.

RoadKill
Jul 5, 2004, 04:10 AM
Oh Man!!

I really hope this is a way forward with the express!! I'm fed up with wires trailing round my living room just for watching the odd dvd. They are never long enough or too long, get damaged... blah blah blah!

I would need to buy another express as the two I am awaiting already spoken for!! Please, please support the dvd player :-)

Jedda
Jul 5, 2004, 04:26 AM
I'm positive i remember steve saying that you can have full 5.1 surround sound using airport express in a recent keynote (pretty sure it was the launch of the Europe iTMS).

Positive.

Nermal
Jul 5, 2004, 04:38 AM
I've you've never heard DVD Audio, then you are missing out, it sounds amazing!

I have a DVD Audio disc, but no player. Apple should add DVD Audio support to their DVD Player app.

cazlar
Jul 5, 2004, 05:07 AM
I don't know about DVD-Audio, but a recent knowledgebase doc (http://docs.info.apple.com/article.html?artnum=93870) mentioned that iTunes will be able to play DTS files though AirTunes, as long as all signal processing (ie equalisers/soundcheck) is turned off.

WinterMute
Jul 5, 2004, 12:13 PM
I don't know about DVD-Audio, but a recent knowledgebase doc (http://docs.info.apple.com/article.html?artnum=93870) mentioned that iTunes will be able to play DTS files though AirTunes, as long as all signal processing (ie equalisers/soundcheck) is turned off.

Now that might be interesting, I can already play 5.1 DTS files directly from CD's in my Denon DVD player, but the optical option to stream 5.1 DTS to my system from my PowerBook is an excellent idea, I can forsee some very useful scenarios in the 5.1 rooms at the Uni, it's always been a problem playing 5.1 files off the PB, as I only have an M-box, I've always had to bounce them to the G5's for playback.

Incidentally, it's sample frequence that is mainly responsible for the difference in sound between analogue and digital, not bit rate, which, as mentioned, acts on dynamic range, the reason DVD-a sounds so good is a sample rate of up to 192Khz, standardising at 24/96.

Nyquist knew what he was talking about. :D

stoid
Jul 5, 2004, 12:21 PM
Could you then theoretically download the latest trailer from apple.com/iTunes and play it back hearing full 5.1 sound via AirTunes? That would be very cool!

MacFan25863
Jul 5, 2004, 02:06 PM
Could you then theoretically download the latest trailer from apple.com/iTunes and play it back hearing full 5.1 sound via AirTunes? That would be very cool!

Only if it is encoded in 5.1. Also, if you were to plan on putting the trailer on a TV, it would look REALLY bad.

jackieonasses
Jul 5, 2004, 02:49 PM
in the WWDC keynote, he mentioned 5.1 with air express. So i guess it does do that.

Jalexster
Jul 5, 2004, 02:56 PM
Lots of PC games have 5.1 sound through EAX. Even Half-Life had EAX, and it's really old. If your sound card gets it's audio from the game in EAX format, it process it as a 3D 5.1 channel soundscape (rather than a 2.1 channel soundscape), and sends it through three 35mm headphone style sockets on your sound card. Or if your card has an SPDIF/Optical (Or whatever it is) output, it will transform it into a Dolby Digital or DTS format signal and output it.

The PowerMac G5 has an optical output, I don't think it supports EAX, so games will have to process thier audio, and encode it in DTS or Dolby Digital in a software encoder, because the soundcard/chips in the G5 dosen't support EAX. I know that DVD-Player can give out a raw DTS or Dolby stream through the G5's optical out.

Systems like the XBox probably use EAX, but it is hidden. Thats how the Dolby Digital output is generated.

I think I am right...

mmmbop
Jul 5, 2004, 04:01 PM
in the WWDC keynote, he mentioned 5.1 with air express. So i guess it does do that.

Is AirTunes system-wide? Or is it just audio through iTunes?

Playing audio through your stereo speakers while watching a DVD would be great, but I'm not sure if DVD Player supports that.

Webcasts through Safari (RealPlayer stuff, too) would be great. Although you would really hear the not-so-hot quality of low-bit streams through any decent stereo.