Audio Midi Setup and 5.1 Surround

JF Mezei

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Oct 1, 2010, 2:00:54 AM10/1/10

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I have a TOSlink cable out my Macpro to a Dolby 5.1 and DTS capable stereo.

VLC has no problem sending digital encoded audio for Dolby 5.1 soundtracks.

But, the Audio Midi Setup application does not let me select 5.1 dolby
output.

In the "configure speakers", all but "Stereo" options (such as 5.1
surround) are greyed out.

I tried various permutations in the main screen (khzm and the number
ochannels m and "encoded digital audio, but none of the permutatiosn
made the optiosn other than "stereo" available.

Has anyone sucesfully gotten Audio Midi Setup to set to have 5.1
speakers ? I remember doing once ion the early days of this Mac, but
only once and since then, I have been unable to do so.

I am now at 10.6.4 I think.

Itunes, despite advertising its standard definition movies as 5.1
surround, seems to send them as simple stereo. Could it be because it
seems my outp7ut as 2 speakers and sends me a stereo version of a movie ?

Malcolm

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Oct 1, 2010, 3:56:11 AM10/1/10

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Multi-channel audio works only through the digital audio output into a
receiver or amplifier that has optical digital input and multi-channel
decoding. Select "Digital Out" in DVD Player's "Disc Setup"
preference, or "Audio Device" in VLC's "Audio" menu.

JF Mezei

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Oct 1, 2010, 6:00:11 AM10/1/10

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Malcolm wrote:
>
> Multi-channel audio works only through the digital audio output into a
> receiver or amplifier that has optical digital input and multi-channel
> decoding. Select "Digital Out" in DVD Player's "Disc Setup"
> preference, or "Audio Device" in VLC's "Audio" menu.

I had gotten VLC to do digital audio a while back. (despite the Audio
Midi Setup refusing to allow it).

But you are right, DVD Player does with with digital audio now.

But what about Quicktime and SD movies purchased/rented from Itunes ?
Can they be played with dolby (or dts) surround ?

And is the Audio Midi Setup "broken" for everyone, or is it just me who
is unable to tell it to use a 5.1 speaker setup ? Or is Audio Midi Setup
no longer used to control audio output ?

Malcolm

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Oct 1, 2010, 4:58:38 PM10/1/10

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If you add multi-channel audio hardware, Audio MIDI Setup will control
it, but the built-in audio is only two-channel, so the only way it can
handle multi-channel is with external decoders.

JF Mezei

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Oct 1, 2010, 7:12:57 PM10/1/10

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Malcolm wrote:

> If you add multi-channel audio hardware, Audio MIDI Setup will control
> it, but the built-in audio is only two-channel, so the only way it can
> handle multi-channel is with external decoders.

So Audio Midi Setup doesn't recognise the built in fibre optic sound
output as capable of multi channel sound ?

Malcolm

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Oct 1, 2010, 9:19:05 PM10/1/10

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The multi-channel sound that does work is just sent directly from the
DVD out the optical port with no processing in the computer, so Audio
MIDI Setup doesn't have to do anything special. All processing is done
in the external decoder.

Kevin McMurtrie

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Oct 1, 2010, 10:37:32 PM10/1/10

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In article <4ca5791c$0$831$c3e8da3$4605...@news.astraweb.com>,
JF Mezei <jfmezei...@vaxination.ca> wrote:

Mac OS X has no support for surround sound. Multimedia applications
typically pass along the original compressed audio stream for the
receiver to decode.

iTunes and QuickTime are supposed to pass through surround audio but the
feature has a long history of not actually working. iTunes 10 makes the
claim again but I'm not going to try it because it takes too long to get
a refund.
--
I won't see Google Groups replies because I must filter them as spam

JF Mezei

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Oct 2, 2010, 1:52:19 AM10/2/10

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Kevin McMurtrie wrote:

> iTunes and QuickTime are supposed to pass through surround audio but the
> feature has a long history of not actually working. iTunes 10 makes the
> claim again but I'm not going to try it because it takes too long to get
> a refund.

I rented a movie , standard definition recently. The itunes store
cleared stated it was dolby 5.1 surround. The "get info" in the itunes
application once the movie downloaded showed it as "stereo". I got
credits for a couple of songs on itunes store.

What I would like to know is whether it is because of my setup or
whether this is for everyone.

I have 2 non apple LCD displays which prevent whatching HD stuff from
the itunes store. Could this also prevent surround sound and Itunes
downsambles everything to stereo ? ( it wouldn.'t surprise me because
this stupid DRM stuff is ... STUPID ....)

Kevin McMurtrie

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Oct 2, 2010, 11:24:22 AM10/2/10

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In article <4ca6c891$0$30022$c3e8da3$76a7...@news.astraweb.com>,
JF Mezei <jfmezei...@vaxination.ca> wrote:

I wouldn't see that as your problem. iTunes has access to your hardware
profile and it works with Quicktime to manage the DRM. If it says you
can rent an HD movie at an extra cost, it should play it or you should
get a refund. iTunes movie rentals haven't worked well for me even with
an HDMI connection to DRM aware TV.

I've been using Netflix and Amazon VOD. Netflix is much cheaper and
Amazon usually looks better.

Malcolm

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Oct 2, 2010, 8:58:21 PM10/2/10

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On 2010-10-02 11:24:22 -0400, Kevin McMurtrie said:

> In article <4ca6c891$0$30022$c3e8da3$76a7...@news.astraweb.com>,
> JF Mezei <jfmezei...@vaxination.ca> wrote:
>
>> Kevin McMurtrie wrote:
>>
>>> iTunes and QuickTime are supposed to pass through surround audio but the
>>> feature has a long history of not actually working. iTunes 10 makes the
>>> claim again but I'm not going to try it because it takes too long to get
>>> a refund.

<http://www.cod3r.com/2008/02/the-correct-way-to-enable-ac3-passthrough-with-quicktime/>