Rsbrsvp Posted June 25, 2021 Share Posted June 25, 2021 This experiment is very impressive. I thank the experimenter. It is a technical test to as accurately as possible determine if bit-perfect sound is streaming in many various conditions- and the tester did a great job. I would like to recommend a somewhat similar but yet very different test. If all the above tests in different formats were redone playing the same music from the same albums- and nobody looked at the bit-perfect light on the dac, but instead a blind listening test was done where the one who controlled the variables was not the one who listened, and the listener took notes to determine which of the many options his ears liked better with NO knowledge of what the operator was playing, I wonder if the listener would choose "bit-perfect or not? I wonder if the listener would choose Qobuz over Apple, or vice versa, etc., etc. The most important key in such a test is the word "BLIND" as psychological factors and biases deeply effect our choices without our realizing. Perhaps, multiple listeners could participate so several sets of ears would be involved in the test to add some credibility to the results. If anyone has the time to do a similar test to the ones above but to use a persons ears instead of a light on a dac as the factor to determine which is better, I think that would be great. I realize this is a NON-objective test and rather one of listening tastes unlike the experiment conducted above and so the conclusions would not at all be sealed in stone, but yet it may be of interest. I realize that no one is implying that bit-perfect is necessarily better than non-bit perfect- just that it is bit-perfect and therefore not modified from how the artist recorded his song; but at the end of the day, if our ears like non-bit perfect better, or apple better than Tidal,- perhaps this is a more important factor- and that is why I recommend this test. After all, audiophiles are generally a combination of music lovers and scientists. But I would hope that we all stress the music loving part over the scientific. Bevok 1 Link to comment
easp Posted June 25, 2021 Share Posted June 25, 2021 Thanks for doing these experiments and writing them up. I know how much work that is, especially when you think of something just as you think you are done and have to revisit a big chunk of work. I really appreciate the insight into behavior of Apple Music on iOS. I've done some tests myself focused on MusicApp on MacOS. I've been looking at the amount of data transferred from Mac to an AirPorts Express v1 and v2 (with the AirPlay2 firmware) in order to identify whether the ALAC codec or the AAC codec is being used. The short answer is that when Apple Music on MacOS is set for lossless playback and playing a track with a lossless version available, it transcodes to AAC when playing directly to an AirPlay 2 receiver. When playing through system audio with the system audio set to the AirPlay 2 receiver, it uses ALAC. With an AirPlay v1 receiver, it switches to an AAC version from Apple's server and then transcodes that to ALAC for transmission. Playback of local ALAC rips uses ALAC transport to AirPlay 2 receivers. This comports with your results. It looks like the lack of bit-perfect playback to AirPlay 2 receivers is due to the use of AAC as the LAN transport codec. I hope Apple will fix this, but the lengths they seem to go to in order to avoid an unbroken lossless stream from their servers to a DAC (internal or external) over AirPlay v1 or v2 makes me think that this is deliberate, perhaps to thwart piracy of lossless files (even though CDs still exist). Link to comment
Popular Post Marco Klobas Posted June 25, 2021 Popular Post Share Posted June 25, 2021 Inspired by the Chris' tests I tried to find a match with his results. I already shared here the tests using a Mac as an AirPlay receiver and recording what the computer was receiving from an iPad. The recordings were compared with the original track I own inverting its phase. The results were: muted sound – the tracks nulled each other. Two software receivers were used: AirServer and Shairport Sync (both AirPlay 1). My previous tests confirmed that the incoming streams from iPad to a Mac acting as an AirPlay 1 device were bit perfect as Chris has shown. Now I repeated the test adding a "Mac self AirPlay streaming": the Mac streaming to itself. Both AirServer and Shairport Sync are visible in Music app. They are not via the volume menu (system-wide). Actually it makes sense: why would a Mac act as a transmitter and receiver at the same time. It's strange that Music app ignore this. To simplify the reading I prepared a scheme with the results: As you can see, when a Mac streams to an AiPlay 1 device (within Music app) the tracks don't null. The last column includes the loopback recording (no AirPlay – simply the Mac recording what is receiving directly via Music app). Basically I can confirm the tests Chris has done regarding the Mac to AirPlay bit perfect issue (AirPlay chosen within Music app). wklie and One and a half 2 Link to comment
Popular Post Marco Klobas Posted June 25, 2021 Popular Post Share Posted June 25, 2021 A quick visual recap of Chris's tests: wklie, Jud and BitPerfect_ 1 2 Link to comment
The Computer Audiophile Posted June 25, 2021 Author Share Posted June 25, 2021 24 minutes ago, Marco Klobas said: A quick visual recap of Chris' tests: Via USB, Apple Music isn’t bit perfect on macOS. Founder of Audiophile Style | My Audio Systems Link to comment
Marco Klobas Posted June 25, 2021 Share Posted June 25, 2021 4 minutes ago, The Computer Audiophile said: Via USB, Apple Music isn’t bit perfect on macOS. Sorry, Chris. You're referring to your first test, isn't it? I've updated the image. Link to comment
The Computer Audiophile Posted June 25, 2021 Author Share Posted June 25, 2021 27 minutes ago, Marco Klobas said: Sorry, Chris. You're referring to your first test, isn't it? I've updated the image. Yeah, it’s confusing. The Music app can play local content via USB but perfect, it not content from Apple Music the streaming service. Marco Klobas 1 Founder of Audiophile Style | My Audio Systems Link to comment
Mike27 Posted June 25, 2021 Share Posted June 25, 2021 I just want to thank everyone, fascinating thread even though I live in MS-world except for the phones. Food for thought here. I had previously struggled with Chrome Audio but eventually gave up. Also you’ve reminded me to ID & decode more HDCD files since I don’t have anything that does it in real time. And the latest additions may have me re-thinking this whole Airplay thing that I rejected years ago. Carry on... Link to comment
new_media Posted June 25, 2021 Share Posted June 25, 2021 31 minutes ago, The Computer Audiophile said: Yeah, it’s confusing. The Music app can play local content via USB but perfect, it not content from Apple Music the streaming service. Chris, if you download the album from Apple Music to a Mac, so you are playing back from locally stored files, do you still not get bit perfect playback over USB? If not, something strange is afoot. I do not get bit perfect playback using an iPad through the USB camera connection kit, but this is true for both my own rips and downloaded Apple Music files. Link to comment
agladstone Posted June 25, 2021 Share Posted June 25, 2021 Does anyone know if the 2nd and/or 3rd Gen original Apple TV with optical out and Ethernet in can receive Airplay 1 and Airplay 2 and work the same as the two gens if airport express Chris used for his testing? I sold my Airport Express long ago, but still have the 2nd and 3rd Gen of the original Apple TV with optical out in a drawer somewhere! Second, anyone know if and how this may work and achieve bit perfect lossless in my new car which has Apple CarPlay? My new car (2021 BMW) has both Bluetooth and also USB data input going into the stock BMW stereo / Infotainment system (iDrive 7) which can play music stored on my iPhone 12 Pro or a exFat USB stick and any locally downloaded offline content from Qobuz seems to be available via CarPlay (so far lossless downloaded Qobuz sounds the best). I’m assuming that regardless of Bluetooth or USB input that the cars system still processing everything via it’s own DSP and DAC, so maybe it’s pointless anyhow??? Link to comment
loop7 Posted June 25, 2021 Share Posted June 25, 2021 The videos are fantastic; the iPad volume test was my favorite. I've caught myself being annoyed by all this a few times but reminded myself we are simply witnessing a company doing it's job. I just hope Qobuz will be around long term. Link to comment
NOMBEDES Posted June 26, 2021 Share Posted June 26, 2021 Excellent work Chris. Thank you In any dispute the intensity of feeling is inversely proportional to the value of the issues at stake ~ Sayre's Law Link to comment
wklie Posted June 26, 2021 Share Posted June 26, 2021 4 hours ago, agladstone said: Does anyone know if the 2nd and/or 3rd Gen original Apple TV with optical out and Ethernet in can receive Airplay 1 and Airplay 2 and work the same as the two gens if airport express Chris used for his testing? If an Apple device runs AirPlay 2, it is never AirPlay 1. However, AirPlay2 can send and receive in two codecs: lossless ALAC and lossy AAC. It's up to the sender to choose whether it wants to send it lossless or lossy (perhaps for enhanced buffering to multi rooom). Peter Lie LUMIN Firmware Lead Link to comment
BitPerfect_ Posted June 26, 2021 Share Posted June 26, 2021 18 hours ago, Marco Klobas said: A quick visual recap of Chris's tests: Thank you for sharing with us this visual conclusion @Marco Klobas and also thank you for dig into this subject @The Computer Audiophile . I have to recognize that I'm not so sure that I can follow properly due to the lack of background informations. Having said that, would you please share with me your opinion in the following case? Apple Music installed on iPhone7, iOS 14.6, streaming using Airplay2 to Yamaha WXC-50, Airplay1. Playing Hi-Res files from Apple Music, will display on mobile up to 24-bit/96kHz ALAC. This looks normal because WXC-50 is a Streamer/DAC able to process ALAC files up to 24-bit/96kHz (not 192kHz). The question is, using this setup, the WXC-50 will receive what Apple Music info box is showing (bit perfect), will downsample or ?! I can't find a track with 24-bit/192kHz (if someone can point me to one, I can test with that file too in order to see what is displayed). I appreciate it! Link to comment
Marco Klobas Posted June 26, 2021 Share Posted June 26, 2021 This is a 192 kHz track: https://music.apple.com/us/album/blues-to-elvin/962196097?i=962196098 What Apple Music displays is what Apple Music offers, which is not necessarily what the user hears. For example I can listed to the above 192 kHz song with my AiPods Pro. The app shows 192 kHz even though I clearly can't listen to 192 kHz due to the limitation of AirPods Pro. AirPlay audio (1 and 2) is a 44.1 kHz protocol. Everything over 44.1 kHz is downsampled. It's not clear if your Yamaha WXC-50 is AirPlay 1 or 2. You stated "using Airplay2 to Yamaha WXC-50, Airplay1". Is it 1 or 2? BitPerfect_ 1 Link to comment
BitPerfect_ Posted June 26, 2021 Share Posted June 26, 2021 Thank you for your feed-back. Yamaha WXC-50 is AirPlay1. The iPhone7 shows the AirPlay2 icon by default, being up to date to iOS 14.6 but getting back to the streamer, I've checked, there is no update to Airplay2 on WXC-50. Coltrane Plays the Blues, it shows as Hi-Res 24-bit/192kHz ALAC indeed but summing up with your statement, it looks like the WXC-50 will receive 16-bit/44.1kHz. So in the end, there is no way to feed the streamer in order to play at Apple Music's delivered rated sample rate? Link to comment
Marco Klobas Posted June 26, 2021 Share Posted June 26, 2021 Since you stream from your iPhone and being the Yamaha WXC-50 an AirPlay 1, it will get a 44.1 kHz bit perfect audio, which is the maximum for AirPlay 1. The AirPlay icon on iOS/iPadOS is currently always shown as AirPlay 2 even when an AirPlay 1 device is involved. I used both AirPlay logos to make visually a better distinction. BitPerfect_ 1 Link to comment
BitPerfect_ Posted June 26, 2021 Share Posted June 26, 2021 Just to clarify, the WXC-50 will receive the maximum delivered by AirPlay1 and will remain at 16-bit/44.1kHz or after that the internal DAC will upsample this signal to 24-bit/96kHz which is the higher WXC's ALAC sample rate before getting to analog? Link to comment
Popular Post Marco Klobas Posted June 26, 2021 Popular Post Share Posted June 26, 2021 That's up to the receiver. I don't think the WXC-50 will upsample. On the Yamaha page is written up to 96 kHz (emphasis is mine). For example, Apple TV resamples everything to 48 kHz because that is its fixed output. BitPerfect_ and JoeyGS 2 Link to comment
photonman Posted June 26, 2021 Share Posted June 26, 2021 Chris, What about the BitPerfect app that sells for $10 and the latest version 3 that supports the new Apple Music app. Would this be a viable setup to get bitperfect out of Apple content? RIG: iFi Zen Stream - Benchmark DAC3 L - LA4 - AHB2 | Paradigm Sig S6 | Cables: anything available Link to comment
Marco Klobas Posted June 26, 2021 Share Posted June 26, 2021 I chime in even if I'm not Chris. 🙂 Unfortunately BitPerfect app doesn't work with Apple Music contents. Only local files (owned) are handled. The Computer Audiophile 1 Link to comment
Popular Post Bevok Posted June 27, 2021 Popular Post Share Posted June 27, 2021 From the Wall Street Journal “Likewise, Apple says it will make its wireless AirPlay system capable of lossless in a future update.” Marco Klobas and BitPerfect_ 1 1 Link to comment
EuroChamp Posted June 27, 2021 Share Posted June 27, 2021 Really great job - thanks for testing Chris! Link to comment
R1200CL Posted June 27, 2021 Share Posted June 27, 2021 What a total mess this is 😀 Apple normally like to keep things simple. Not so this time it seems. lucretius 1 Link to comment
BitPerfect_ Posted June 28, 2021 Share Posted June 28, 2021 On 6/27/2021 at 7:25 AM, Bevok said: From the Wall Street Journal “Likewise, Apple says it will make its wireless AirPlay system capable of lossless in a future update.” Q: if the Airplay will be updated to Hi-Res, and I guess that we are talking about a new version (maybe) those with Airplay1 devices will be able to receive the higher bitrate or the unit will remain @16-bit/44.1kHz and it's time to upgrade the hardware system? I am trying to understand if the limitation it's on the receiver too. Thanks, Link to comment
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