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yoyoman · Jun 24, 2003, 12:31 PM

thats a oxi moron.Optical digital audio
how can something be optical and digial. 5.1 windows has 6.1 and 7.1

gregomni · Jun 24, 2003, 12:37 PM

Originally posted by yoyoman:
thats a oxi moron.Optical digital audio
how can something be optical and digial.

dig�i�tal
adj. Expressed in numerical form, especially for use by a computer.

op�ti�cal
adj. Relating to or using visible light.

Optical digital audio: Audio expressed in numerical form and transmitted using visible light.

Taipan · Jun 24, 2003, 12:46 PM

Originally posted by yoyoman:
thats a oxi moron.Optical digital audio
how can something be optical and digial. 5.1 windows has 6.1 and 7.1

Hi!

I'm no expert in this, but if data consisting of 1s and 0s is transferred by light going on and off, it's digital and optical, isn't it?

Powaqqatsi · Jun 24, 2003, 12:51 PM

Originally posted by yoyoman:
thats a oxi moron.Optical digital audio
how can something be optical and digial. 5.1 windows has 6.1 and 7.1

Errr, it's quite correct

digital = 1 & 0 and optical is transfer with light (the type of cable). The 5.1 , 6.1 and 7.1 don't have anything to do with it.

yoyoman · Jun 24, 2003, 02:02 PM

Originally posted by Powaqqatsi:
Errr, it's quite correct digital = 1 & 0 and optical is transfer with light (the type of cable). The 5.1 , 6.1 and 7.1 don't have anything to do with it.

so can apple use 6.1 and 7.1. what about the g4 what was its max. i thnk it wasnt even 3.1

Eriamjh · Jun 24, 2003, 02:03 PM

Actually, if the G5 mac has optical digital out (it could have optical analog out which doesn't really exist in the audio world or COAXIAL digital out which is another connection method) then it can probably can stream the 6.1 audio streams off of DVD and games that support it.

5.1 is commonly a reference to Dolby Digital autio compression (formerly known as Dolby AC-3). Any digital streaming device can stream any digital data regardless of whether it's 5.1, 6.1, 7.1 or some future standard (I've head Sony's SDDS is capable of up to 9.1 channels!)

So, in essence, these macs will have 6.1 and 7.1 since the decoding is all done off-board of the mac in the audio processor.

KidRed · Jun 24, 2003, 02:10 PM

Originally posted by yoyoman:
thats a oxi moron.Optical digital audio
how can something be optical and digial. 5.1 windows has 6.1 and 7.1

Don't have a modern receiver hooked up to a HDTV do you?

zigzag · Jun 24, 2003, 02:14 PM

Originally posted by yoyoman:
so can apple use 6.1 and 7.1. what about the g4 what was its max. i thnk it wasnt even 3.1

Optical is just a method of transmitting the digital information, doesn't matter if it's 3.1 or 10.1.

Michel_80 · Jun 24, 2003, 03:41 PM

I hope (and it should) that it is possible to play back AC3 or even DTS? Is it confirmed that Ac3 and DTS standards can be played back to recievers using the Optical audio out?

tooki · Jun 24, 2003, 03:44 PM

Yup. The speakers Apple sells for these things is a 5.1 Logitech system with optical input and a built-in AC-3 and DTS decoder.

tooki

exa · Jun 24, 2003, 03:47 PM

Well, this must mean Apple DVD player is finally going to support 5.1 sound... right?!

tooki · Jun 24, 2003, 03:48 PM

I'll let you know when I buy my G5!

tooki

Michel_80 · Jun 24, 2003, 03:58 PM

So what, Apple had no AC3 playback so far???

I have an old P3 500 desktop which has got an SPDIF out so I can watch T2 with some nice effect

tooki · Jun 24, 2003, 04:23 PM

Alas, no, Apple has never had anything better than plain-vanilla stereo till now. Multichannel audio cards (and external USB audio interfaces) exist, but Apple's current DVD Player only supports 2 channel sound, downmixed to Dolby Surround, with no DTS support at all. Presumably Panther (if not 10.2.7) will include a new version of the DVD player that supports better audio. (Current users of multichannel audio interfaces on the Mac had to rely on vlc to play DVDs with multichannel audio. vlc is a capable, but extremely processor-intensive video player which also is in need of interface refinement -- it's pretty, but often very unresponsive.)

tooki

Tutman · 08:35 AM

Well, it's true that Apple has been slow to offer multi-channel output both in terms of hardware and software. But like tooki writes, 5.1 sound has been possible for some time with third party products.

First, you need an interface that will allow you to stream DTS- or AC3-encoded material digitally (through optical or coaxial connections). There are quite a few PCI-cards, USB- and Firewire-solutions in all price ranges that do this. Some of them include their own decoders, others just pass the digital signal to a home cinema amplifier.

Then you need software that play back the multi-channel material through your digital output. And no, Apples DVD player doesn't do this, yet. But VLC do (though I agree on the limitations mentioned above).

And if just want to play raw DTS and AC3 files for external decoding, many programs will do this (Apple has described a professional setup where PowerPoint outputs DTS-encoded multi-channel audio in this article).

But with the G5 it of course gets a lot easier. And I think we can bet on multi-channel output in the DVD player that will come with Panther (but you still need an external decoder, multi-channel amp and speakers, of course - the Logitech/Alesis system mentioned above looks interesting).

Multi-channel audio support is also promised for an upcoming QuickTime release. Macbidouille even claims there are rumours about 5.1-support in iTunes 5, which reportedly also will play DVD-Audio discs.

Cool.

silverlode · Jul 15, 2003, 04:41 PM

iTunes playing DVD-Audio...hmmm.... I wonder, do the MP3 or AAC formats support compression of more-than-2-channel audio?

Tutman · Jul 15, 2003, 06:25 PM

I wonder, do the MP3 or AAC formats support compression of more-than-2-channel audio? [/B]

AAC can do it, and QuickTime will soon be able to support any number of channels and route them to any number of speakers.

For more on this, tune in towards the end of Apple's QuickTime State of the Union address from the recent WWDC.

This of course doesn't mean that the rumor is true...

Tutman · Sep 30, 2003, 12:46 PM

Somewhat related: AppleInsider is reporting that recent pre-release builds of Apple DVD Player 4.0 has support for digital 5.1 output through the built-in S/PDIF port of the Power Mac G5.

jamesa · Oct 1, 2003, 06:58 AM

Originally posted by Tutman:
Somewhat related: AppleInsider is reporting that recent pre-release builds of Apple DVD Player 4.0 has support for digital 5.1 output through the built-in S/PDIF port of the Power Mac G5.

which will mean that it simply outputs the sound for processing by a pre-processor or home cinema receiver. If your receiver supports DTS/AC3/Dolby Digital, then it should play.

This is of course reliant on no nasty eccentricities in Apple's software. Tooki should be able to confirm it for us... if he has a recent copy of Panther...

Also, DVD-A will not be possible over the SPDIF port. Until SDMI is ratified, DVD-A must be decoded into analogue before passed into your receiver/processor (unless you've got an expensive set up - something like Meridian). The only possible option would be to get a card that does analogue output - like that M-Audio Revolution 7.1 job.

cheers,

-- james

dfiler · Oct 1, 2003, 01:46 PM

Originally posted by yoyoman:
thats a oxi moron.Optical digital audio
how can something be optical and digial. 5.1 windows has 6.1 and 7.1

Ooo... I love posting on this topic.

Not all digital outputs are optical. Not even all optical outputs are digital Although, you'd be hard pressed to find one of these analog+optical devices. Furthermore, I think you were looking for the word redundant.

As to 6.1 and 7.1 ...

They are actually delivered in such a way that the formats are 100.0% backward compatible with 5.1

7.1 is the exact same signal as 6.1 but you simply put two speakers on the rear-surround channel.

There are two types of 6.1, discrete and matrixed. Matrixed 6.1 is a pure 5.1 signal in which the audio engineers recorded a matrixed rear surround channel. It is transmitted as a 5.1 signal.

6.1 discrete delivers a signal compatible with 5.1 equipment but adds a completely seperate rear surround channel. This signal is also matrixed back out of the left and right surrounds when played on 6.1 capable gear.

So... yes, apple supports all of these formats over their non-oximoronic and non-redundently titled optical digital out.

klinux · Oct 1, 2003, 02:19 PM

Summary II: Apple is still disappointedly behind in surround sound audio.

RayX · Oct 2, 2003, 11:01 PM

Originally posted by klinux:
Summary II: Apple is still disappointedly behind in surround sound audio.

Panther will fix this.

If you have a G5 with Panther you are ready to go, any other hardware, just need a cheap USB to S/PDIF device, or a sound card with optical or coax outputs.