![]() Test 2, streaming the Reference Recording's album Exactly Like This from Doug MacLeod, displays different behavior and bolsters my aforementioned watermarking theory. I'm open to all input on what this could possibly be, but watermarking is my best educated guess for now. Apple has a perfect copy of the album on its servers, the perfect copy starts, but then something changes in the stream that causes the music to not be bit perfect. ![]() If I had to guess, I'd say this is because of watermarking mandated by the major record labels. When I clicked the play button to start the entire album over again, the HDCD indicator illuminated again for a few seconds. After this, the light went out for good, even if I skipped to the next track. ![]() Test 1, streaming Pearl Jam's Live On Two Legs release I was able to illuminate the HDCD indicator for the first couple seconds of playback. In addition to a couple other nonsensical issues that I'll get into later, Apple is doing something to the music it streams. On macOS, I found no way to play bit perfect lossless or Hi-Res audio from Apple Music. If anyone can identify a hole, please let me know and I will retest. It's the same music on all the services that offer lossless streaming.Ībsolutely there are possible holes in my methodology, but I believe I've minimized them as much as possible. Again, there are no alternative versions of these lossless albums. On iOS, I used used other apps such as Qobuz, to play the identical music through the identical hardware. I played some Reference Recordings albums through Apple Music on macOS and made sure the app could handle bit perfect playback. I set a baseline by playing my own local copy of the albums and make sure the HDCD indicator illuminates. Pearl Jam's Live On Two Legs was only released as an HDCD master for its lossless CD version. For example, Reference Recordings only releases CDs that are HDCD encoded. Many of these albums were only released as HDCD encoded CDs/files. I have a list of roughly ten known HDCD albums (although I could use more if needed). With respect to source files, here's what I do. Apple Music's lossless audio that I tested was 16 bit / 44.1 kHa and the Hi-Res audio was both 24 bit / 176.4 kHz and 24 bit / 192 kHz. changes this least significant bit and won't enable the HDCD indicator to illuminate on my DAC. Any alteration, DSP, volume leveling, etc. The HDCD flag is on the 16th bit for lossless CD files and the 24th bit for high resolution files. When an unaltered HDCD music track is played, the HDCD indicator on the DAC is illuminated. I use a Berkeley Audio Design Alpha DAC Reference Series 3 that identifies and decodes HDCD on all sample rates from 44.1 up through 192 kHz. The USB audio interface is a Berkeley Audio Design Alpha USB that accepts USB input and outputs audio over AES/EBU or S/PDIF (BNC). I use the following testing methodology to test Apple Music. I connected the newest version of the Apple Camera Connection Kit to the iPhone, so I could attach a USB Audi interface, and feed power to the phone and interface.Īpple Mac Mini (M1) running macOS 11.4, and Apple Pro Display XDR, and USB audio interface connected to the ports on the back of the display. My Apple iPhone 12 Pro running iOS 14.6 and the Apple Music app. If this isn't a concern for you, no worries. ![]() then you should care about bit perfect because without it you have no idea what's happening to your audio. If you care about high quality, getting the lossless streaming you're paying for from Apple Music, Qobuz, Tidal, Amazon Music, etc. The source is what has been delivered to Apple by the record labels. The music sent, in this case from Apple Music, into the playback device hasn't been altered. What is bit perfect and why should I care? In the simplest terms, bit perfect means that the audio hasn't been changed. I'm just making sure I can play the music in its original form and that Apple is sending true lossless and Hi-Res to my audio devices. Whether or not people can hear the difference is a topic for another discussion. If Apple Music says it's streaming lossless audio, then I want to stream that audio losslessly, rather than accidentally converting it to lossy AAC or MP3 etc. In my tests, I'm only concerned with playing the music bit perfectly, in other words without making any changes to the audio. This morning I've been testing Apple Music's new lossless and Hi-Res offerings on both my iPhone 12 Pro running iOS 14.6 and my Mac Mini (M1) running macOS 11.4. ![]()
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