Why is Masters track getting downsampled?

John_Mesberg · May 9, 2019, 1:33pm

Here is what I’m seeing when I am playing an MQA 96kHz track to my Hegel Rost over Airplay.

My setup:

Roon Core running on iMac (core i7)
iMac connecting over wifi (Google Wifi mesh)
Hegel Rost amplifier connected to one of the Google wifi mesh devices
Note: Hegel Rost DAC is fully capable of handling 24/96 content.

My only current hypotheses are that somehow this is a limit of Airplay (though I’ve not seen any info online which suggests that to be the case) or perhaps a limit of my wifi setup.

Eventually I’ll get a Roon Rock and connect it directly to the Rost but any thoughts as to why I’m seeing this downsampling?

DrTone · May 9, 2019, 1:35pm

You definitely won’t get 96kHz with Airplay as it’s limited to 48kHz. Not sure why it’s being converted down to 44.1 though.

John_Mesberg · May 9, 2019, 1:37pm

Thanks for quick reply. Yeah the downsampling to 44.1 is confusing. Does Airplay limitation also affect the bit depth, i.e. explain why 24bit is going to 16bit?

DrTone · May 9, 2019, 1:40pm

Yes it is limited to 16 bit. Airplay 2 might support 24bit but I’m not sure about higher sample rates.

John_Mesberg · May 9, 2019, 1:41pm

so sounds like its time for a Roon Rock!

ged_hickman1 · May 9, 2019, 1:42pm

I think airplay for audio only is 44.1 - 48 only applies to audio in Video.

http://geekout.io/index_files/The_truth_about_AirPlay_audio_streams.html

wklie · May 9, 2019, 4:09pm

Yes, AirPlay for audio is 16/44.1