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mikebrady / shairport-sync

AirPlay and AirPlay 2 audio player
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24/96kHz support #30

Closed skuligowski closed 9 years ago

skuligowski commented 9 years ago

Hi Mike,

I have IQAudio Pi-DAC+ which supports 24/96kHz audio. Is it possible to configure the shaiport-sync that it can use this high quality settings? Now the airplay port is seen by all devices as 16bit/44kHz output device.

Thanks for the response and keep up that great work!

mikebrady commented 9 years ago

Hi there. I have a Pi-DAC myself and it is impressive, indeed. Shairport Sync only supports 16/44.1 mode. I don't have plans for support of different sample rates or depths. The ALAC to PCM decoder in Shairport Sync is set to 44.1/16 though apparently changeable in principle. It's not clear to me what benefits transcoding in software would bring. If Apple moved to different rates, of course, that would be interesting.

stigger commented 9 years ago

Apparently, Apple supports 96/24: https://discussions.apple.com/thread/2630381

mikebrady commented 9 years ago

Thanks for that. I had a look, and it seems that they only support 44.1/16 over AirPlay at present. Is that a fair reading of it?

stigger commented 9 years ago

Sorry, was too excited by one of the first replies and did not read carefully the rest :(. You are right, 44.1/16 it is.

ghost commented 9 years ago

Hi Mike, Any chance on getting shairport-sync to run on more than 16bit/44.1KHz? Looking for 24/96 tbh. 24 x 96000 x 2channels = 4.6Mbps so a modern N band wifi setup should work. Is it too hard to do? I presume there are lots of people that would love this feature.

mikebrady commented 9 years ago

Hi there. It seems that all sources are converted to 44.1/16 before being sent to an AirPlay device, so there doesn't really seem to be much reason to got to 24 bit or 96k as shairport sync would be doing the conversion. Of course, Apple might introduce a different standard – there doesn't seem to be a technical reason why not. But until they do, there really doesn't seem to be any point.

qerub commented 8 years ago

@mikebrady: One reason I can see for going 24 bit is that it would give Shairport's software volume control more headroom allowing users to lower the volume without any significant degradation of the output signal.

mikebrady commented 8 years ago

I completely agree, and it's especially true when you add in dither! I'm trying to figure out how to do a general solution, including 32 bit and proper endianness. Thanks for your ideas!

qerub commented 8 years ago

@mikebrady: Excellent!

By the way: Please consider accepting donations for shairport-sync (through PayPal or similar); I believe we're many who really appreciate your work.

ghost commented 8 years ago

I'd chip in a few beers, yes.

On 13/12/15 17:34, Christoffer Sawicki wrote:

@mikebrady https://github.com/mikebrady: Excellent!

By the way: Please consider accepting donations for shairport-sync (through PayPal or similar); I believe we're many who really appreciate your work.

— Reply to this email directly or view it on GitHub https://github.com/mikebrady/shairport-sync/issues/30#issuecomment-164268314.