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Airplay & downsampling

My Itunes library contains a lot of 96khz 24bit apple lossless tracks. Currently, when I play this music through Airtunes to my Airport Express, the music is downsampled to CD quality (44,1 khz 16 bit). I think this is done by Itunes. Because the Airport Express architecture can only handle 44.1/16, this is logical and no issue. Itunes itself however is perfectly able to play 96/24 music without downsampling: through the digital output of the Imac, Itunes outputs 96/24 music. So the downsampling only occurs when streaming my music via Airtunes.

Now I have a new media player: the Marantz NA7004. This player can handle high res music, up to 192 khz 24 bit. Next month, this player will be Airplay certified (Airplay is the successor to Airtunes). So then I will be able to stream my Itunes music via Airplay directly to the Marantz NA7004 thereby replacing my Airport Express.

My question is, if Airplay also is limited to CD quality music (like Airtunes is). So, will Itunes downsample my 96/24 music when I stream via Airplay to a airplay certified device?
Bump!

I have exactly the same device and the same question.

Will AirPlay stream up to 96/24 or 192/24 or will it downsample everything to 44/16 even if the receiving device is caple of higher resolution playback?

And one more question:

I guess AirPlay will stream not only wireless but also over a cabled network?
Question: "Will AirPlay stream up to 96/24 or 192/24 or will it downsample everything to 44/16 even if the receiving device is caple of higher resolution playback?"

Answer: Airplay will stream the 24/96 content to receiving devices like the Marantz NA7004, but only from your computer, not from one of the portable Apple devices. Those portable devices, like the iPhone and iPad are internally limited to 16/44. You can use your iPhone or iPad to control the content streaming from the computer to the receiver.

Also, when you listen to music on an iPhone or iPod, the music is not at the 16/44 resolution, it is lower. Apple provides a DAC in each device that does not deliver the full 16/44 resolution. 16/44 is equivalent to CD quality and the Apple Lossless format. If you want that quality from your iPhone, iPod or iPad then you need an external digital dock that decrypts the USB output and converts it at 16/44. Some of the docks available can process up to 24/192, but the iPhone, etc. are still going to restrict you to 16/44 maximum.

You can also use a streaming system over wifi from you iTunes library directly to your iPhone or iPad. Try Zumocast for that, but again, limited to 16/44 and you would need the digital dock as well to get that resolution.
My question relates to streaming to an Airport Express that is connected via Toslink to an external DAC (Cambridge Dac Magic). Can the Airport Express handle 96 or 192 khz. So far I can see on the external DAC that signals are only received at 44.1khz, irregardless of the file being played.
Up.
Same question.

Would somebody reply to this please.

- Is AirPlay 24/96 capable ? Or even 24/192 ?
- Is the ATV2 capable of providing this 24/192 signal out through the optical out, or hdmi (so doing better than the 16/44 limitation of the Airport Express).

This is an important matter that would open new possibilities for audiophile users.
Thanks a lot.

David
CypherLabs wrote:
Question: "Will AirPlay stream up to 96/24 or 192/24 or will it downsample everything to 44/16 even if the receiving device is caple of higher resolution playback?"

Answer: Airplay will stream the 24/96 content to receiving devices like the Marantz NA7004, but only from your computer, not from one of the portable Apple devices. Those portable devices, like the iPhone and iPad are internally limited to 16/44. You can use your iPhone or iPad to control the content streaming from the computer to the receiver.


CypherLabs,
theoretically you have answered it all with the above. I've been researching on this question for weeks now and you came up with the only clear and precise answer so far. However, how do you know? Are there any tech sheets available on that matter?

I have doubts, as I have to admit and here's why: my observation with the new Apple TV 2G is a limitation to 48 kHz. No matter what music iTunes is streaming from my Mac, the output signal of the ATV's Toslink is 48 kHz. My DAC is showing the input signal's frequency, that's why I can tell.

Curly MC wrote:
My Itunes library contains a lot of 96khz 24bit apple lossless tracks. Currently, when I play this music through Airtunes to my Airport Express, the music is downsampled to CD quality (44,1 khz 16 bit). I think this is done by Itunes. Because the Airport Express architecture can only handle 44.1/16, this is logical and no issue. Itunes itself however is perfectly able to play 96/24 music without downsampling: through the digital output of the Imac, Itunes outputs 96/24 music. So the downsampling only occurs when streaming my music via Airtunes.


Curly MC,
are you sure that iTunes is able to output high resolution audio? I'm asking because that would render plugins like Channel D's Pure Music or Sonic Studio's Amarra rather superfluous, I guess. Their claim is just that - deliver high resolution iTunes music to the USB port. But maybe I am missing something here - having just bought one of those plugins I would certainly hope so.
Dear Muwain,
It is my understanding that itunes can play 24/96 files since it can correctly indentify and read them (ALAC files, not FLAC files).
Then the digital out of the mac is also 24/96 capable. To check that, make a toslink connection to your DAC and go to the midi settings of our Mac (Applications/Utilities/Audio Midi Set Up). There you can enter the parameters to 24/96 (not 24/192). Your Dac should confirm that the output actually matches this.

Now the question is : Does Airplay also support that aswell and is the ATV2 able to feed an external Dac with this signal without downsampling.

Anybody has an answer to this ?
Same, exact, unanswered question. What are the physical limitations of Airplay, Airport Express modules, and any other Airplay hardware as related to handling of lossless, high bitrate material? MP3s and AACs are a waste of space at this point, and if Apple is so caught up with HD video why are they not equally focused on high def audio? It takes far less bandwidth... Hey Mr. Jobs! Check out that 24/96 vinyl rip of The Eagles' Long Run and tell me that AAC sounds the same.
Yes I too am very interested in a definitive answer to this subject. Having both Cambridge and Bryston DAC's I would very much like to take full advantage of their capabilities.

Tx
Drew
Bump - I am curious too, thinking of getting a Marantz NA7004 myself.

A correction and a caution to what CypherLabs wrote first:
(1) iPods (and presumably phones) can accept Apple Lossless files at up to 24bit,48khz resolution. They only refuse to accept 96khz. I regularly downsample hires vinyl rips to 48khz for inclusion in iTunes for this reason.

(2) iPod DACs are surely not the best in the world, but I seriously doubt that "Apple provides a DAC in each device that does not deliver the full 16/44 resolution", at least if you mean that the DAC throws away bits or downsamples prior to conversion to analog. 1st gen CD players only decoded the top 14 bits, but that is ANCIENT history, and there is no reason why iPod DACs should do anything like that. Maybe CypherLabs just meant that, after putting the signal through the analog output circuitry, the sound is effectively lower-than-16/44 res. That would no doubt be true, but the same will be true of many cheap CD, DVD and Blu-Ray players' outputs!

Now... any answer re the original question??
bump again

How does audio from itunes plus a receiver with built-in airplay (such as the Marantz sr7005) compare to audio from the same receiver using airport express?
Double, double Bump.
Anybody from Apple on this ?

I would be very interested in knowing if apple tv is able to stream 96kHz 24 bits trough it's toslink output.

Triple Bump!

 

--> still nobody out there, who tried to "AirPlay" HiRes-Audio-Streams from iTunes to Apple TV (2) ???

 

Maybe I'll be able to help all of you next week ... because then I'll get:

- Musical Fidelity M1 DAC (which shows the incoming sample rate)

- Apple TV (2)

- ... and I already have several 24 Bit / 96 kHz Audio-Tracks in my iTunes library (which are not synched to iPods/iPhones - for those are not capable of playing them (iTunes is telling me this).

 

I'll also try to play directly over USB and/orr TosLink Output from my MB Pro (Version 2009) ...

 

Maybe somebody can tell already if this is going to work(?)

Hi All,

 

I think, I can bring some clarity/facts to this issue now :-) - since I own(ed) the relevant devices and actually TESTED this ...

 

Setup:

- Apple MB Pro (OS: Mac OS X & Windows 7) - iTunes-"Server"

- Apple TV 2, connected via TosLinke to ...

- ... Musical Fidelity M1 DAC (which ist limited to 24/96 via TosLink connection)

- Amp Creek Audio Evolution 5350 --> PlayBack...

 

 

(1) Unfortunately: NO. AppleTV 2 is NOT capable of streaming Hi-Res (24/96 oder 24/192) Files (in any format) from your Computer/iTunes library to your D/A Converter via AirPlay. Since the M1 DAC shows the "incoming" sample rate, you can see, ATV2 ALWAYS send at 48 kHz - no matter what sample rate / BitRate your source files are (in other words: ATV2 WILL stream the data, but not in the correct *lossless* format).

--> this is, why I already returned this device "back to sender" ;-(

 

(2) MB Pro IS capable of providing a "real" 24/96 connection via TosLink (optical cable) and a DIRECT connection to the DAC (and I feel the sound is "crispier" this way - just sounds that bit better than streamed via AirPlay). And, BTW, this is fact for OS X as well as Win 7.

 

(3) Since I now need a different solution (I have a lot of HiRes stuff in my iTunes library), I'll also return the (very good sounding!) M1 DAC and buy a "Marantz NA7004" Network Player with integrated AirPlay ability.

--> I've already read in a forum, THIS device WILL stream audio-content via AirPlay up to 24/192(!).

--> As soon as I get the device I will keep you informed ... (anybody still interested in this?).

 

Hope this helped some of you ...

 

Best regards

最後更新：2017-10-05 12:08:16

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