Jump to content
  • The Computer Audiophile
    The Computer Audiophile

    UPDATE: Amazon Music HD Is Still Lossy*

     

    Last month I wrote about Amazon's issues with streaming lossless audio (link). The company advertises high definition, yet doesn't offer lossless CD or HD audio. At the encouragement of a few Audiophile Style readers, I obtained a Bluesound Node 2i for testing. The Node 2i enabled me to test streaming from Amazon without using any of Amazon's applications for Windows, macOS, or iOS. The audio routs from Amazon's servers, through the Bluesound Node 2i's coaxial digital output and into my DAC. I could've use analog outputs in the Node 2i, but for the sake of testing the digital outputs were required. Below are my testing methodology and my findings. 

     

     

    Testing Methodology 

     

    I use a Berkeley Audio Design Alpha DAC Reference Series 3 that identifies and decodes HDCD on all sample rates. When an unaltered HDCD file is played, the HDCD indicator on the DAC is illuminated. The HDCD flag is on the 16 bit for CD files and the 24th bit for high resolution files. Any alteration, DSP, volume leveling, etc... changes this least significant bit and won't enable the HDCD indicator to illuminate. That's the hardware piece. 
     
    With respect to source files, here's what I do. 
     
    I have a list of roughly ten known HDCD albums (although I could use more if needed). Many of these albums were only released as HDCD encoded CDs/files. There is no alternate lossless version. For example, Reference Recordings only releases music that's HDCD encoded. 
     
    I set a baseline by playing my own local copy of the albums and make sure the HDCD indicator illuminates.

     

    I used the Bluesound applications on iOS and macOS for playback during this test. Outside of the Amazon native apps, that I tested previously, the Bluesound app/ecosystem is one of the only systems to integrate Amazon Music HD and stream content up through 24/192. 

     

    Through the Bluesound app and Node 2i combination, I streamed my known HDCD releases first through Qobuz, then through Tidal, and finally through Amazon Music HD. I wanted to use my local file baseline, then two streaming service baselines, before testing Amazon.  

     

    Absolutely there are possible holes in my methodology, but I believe I've minimized them as much as possible. The two major ones are source material. Sure Amazon could have different source material from all other lossless streaming services, but after checking with labels, I highly doubt this is the case. The second one is Amazon's adaptive bit rate. Amazon could be sending me lossy versions of the files and sending other people lossless versions, but I think this is highly unlikely as well. I have a 1 gigabit upload/download unmetered fiber internet connection. I routinely check the speed and see between 800 Mbps and 940 Mbps. If Amazon doesn't think this is a fast enough connection for lossless audio, then I doubt anyone else is going to receive lossless audio, thus making the platform lossy. 

     


    Results

     

    Good news for Bluesound! The Bluesound Node 2i successfully streamed lossless audio from Amazon Music HD from 16 bit / 44.1 kHz up through 24 bit / 192 kHz. Amazon's own apps are unable to do what the Bluesound ecosystem can do with respect to playing the highest quality lossless audio. 

     

    I used the following music to test, and discovered a couple interesting items along the way. 

     

    Neil Young's Greatest Hits, Harvest (2009 Remaster) and After The Gold Rush (2009 Remaster) were all bit perfect at 24/192 from Amazon. 

    Pearl Jam's Live On Two Legs, Beach Boys' Pet Sounds, and Minnesota Orchestra's Bolero! (Reference Recordings) were bit perfect at 16/44.1 from Amazon.

     

    Jewel's album Spirit never illuminated the HDCD indicator on my Berkeley Audio Design DAC through Amazon, but the same Album lit the light through Qobuz. 

     

    The Chicks album Wide Open Spaces was an HDCD master when originally released at 16/44.1. Neither Amazon, Tidal, nor Qobuz streamed a version that illuminated the HDCD indicator on my DAC. There is a 24/96 non-HDCD version available for streaming and I wonder if the 44.1 version is derived from that or if the streaming services have a "bad" copy of the original, or if when the 96 kHz version was done, a 44.1 version was also made and delivered to the services. 

     

    I also found what may be the effects of watermarking on a couple albums I tested. The album No Name Face from Lifehouse and the album Pull My Chain from Toby Keith were originally released as HDCD masters on CD. Playing these albums from Amazon Music HD, the HDCD indicator illuminated for about 1 second, then went dark. I've talked to a few people about this behavior and the agreement seems to be that there's a watermark placed on the albums. The watermark didn't effect the first second of the track, but kicks in shortly after, destroying bit perfect playback. 

     

    Upon further investigation I found:

     

    • Qobuz plays these albums perfectly and lights the HDCD light on my DAC. 
    • Tidal plays the Toby Keith album perfect, but not the Lifehouse album. 
    • Amazon plays neither album perfectly, however Amazon offers a second version of Pull My Chain that does stream perfectly and illuminates the HDCD indicator. 

     

    If the watermark is done at the label level this makes a little more sense. The versions that don't playback perfectly are all labeled SKG / Dreamworks. The Amazon version that doesn't have issues is labeled UMG / Dreamworks. Yes, I realize this is a tiny difference in metadata that may mean nothing, but it's the only difference between the albums that playback perfect the those that don't.

     

    Last, I found some MQA content streaming through Amazon Music HD. It's bit perfect as MQA was displayed on my DAC.

     


    Bottom Line

     

    The bottom line is twofold. First, it's great that Amazon Music HD can be streamed to a HiFi system losslessly in high resolution. Amazon's own applications are incapable of this, but fortunately the indispensable Bluesound Node 2i handles it with ease. If readers want Amazon Music HD, the Node 2i is a requirement in my book. Second, all of this testing indicates that streaming can be a mess for those of us who like high quality and care about the best sound possible. I think of all the conversations I've had with people who say one streaming service sounds better than another or their local copies of albums sound better than the identical versions when streamed. I completely understand. It's a mess out there.

     

     



    User Feedback

    Recommended Comments



    I bought a Node 2i, and it's terrific for Qobuz when played through a good but modest system (Bifrost, NAD, B&W CM-1), but could not come close to matching local files on my primary system (Yggy, McIntosh, B&W 805).  When everything needs to be perfect, streaming is not (yet...)

    Share this comment


    Link to comment
    Share on other sites

    As I said before, it is a sad state that as we get closer and closer to the holy grail of being able to reproduce the musical experience, the music suppliers play games with the source music.

    Share this comment


    Link to comment
    Share on other sites

    @The Computer Audiophile

     

    My hunch was correct - it's just an issue with Amazon's apps (desktop and mobile)...

     

    All they need is to do is workout proper 'Exclusive Mode' which they still haven't figured out. It's there but not working correctly. 

     

    Glad to see my nagging you to get a Node 2i (to bypass their apps) worked well.

     

    Thanks for testing this. I don't have Amazon Music HD in my country to test.

     

    Maybe for a different review but I've read a lot about how shit Amazon Music HD is to use via the Bluesound, compared to their desktop apps, in terms of UI / UX.

     

    And this is no fault of Bluesound - on their forum they say they are constantly asking Amazon for better API support but hearing nothing back.

    Share this comment


    Link to comment
    Share on other sites
    5 hours ago, whell said:

     

    Interesting that you found MQA content on Amazon.  Which album lit the MQA indictor?  Was it one of the albums mentioned above?  Had no idea that Amazon was working with Bob Stuart and company.

     

     

    It's the same issue with Qobuz , like with 2L recordings

     

    Chris tested a couple 2L albums for me in the MQA thread.

     

    So it's a label thing not streaming service thing

    Share this comment


    Link to comment
    Share on other sites

    Man, I'm confused.  Have the Amazon app on my music Mac Mini, pay for HD version, and who I played a couple of new albums yesterday - Dave Grissom's, Matt Scofield's and a tune by Scary Goldings with Josh Smith (I like guitar).  It all sounded pretty nice and my Mytek B+ displayed that the files fed by USB from Mini to B+ were CD quality? 

     

    Not sure how to find stuff on Amazon Music HD that is higher resolution than CD quality to test? 

     

    FWIW, the Mini is connected to the web by WiFi (Netgear hub is in next room, 6 ft linear from the Mini).

     

     

    Share this comment


    Link to comment
    Share on other sites
    4 hours ago, 57gold said:

    Man, I'm confused.  Have the Amazon app on my music Mac Mini, pay for HD version, and who I played a couple of new albums yesterday - Dave Grissom's, Matt Scofield's and a tune by Scary Goldings with Josh Smith (I like guitar).  It all sounded pretty nice and my Mytek B+ displayed that the files fed by USB from Mini to B+ were CD quality? 

     

    Not sure how to find stuff on Amazon Music HD that is higher resolution than CD quality to test? 

     

    FWIW, the Mini is connected to the web by WiFi (Netgear hub is in next room, 6 ft linear from the Mini).

     

     

    The issue is the Amazon app sends it to Windows mixer where it gets altered. If you set your Windows mixer to hi-res then it will stay in that sample rate. Still won't be bit perfect.

    Share this comment


    Link to comment
    Share on other sites

    There's actually one positive with Amazon having some MQA stuff there.

     

    For those with MQA DACs, it's a great bit perfect test, for when Amazon get their desktop and mobile apps properly sorted.

     

    That's about the only good thing MQA is good for. You won't get the MQA indicator on your DAC unless playback is bit perfect.

     

     

    Share this comment


    Link to comment
    Share on other sites
    7 hours ago, 57gold said:

    Man, I'm confused.  Have the Amazon app on my music Mac Mini, pay for HD version, and who I played a couple of new albums yesterday - Dave Grissom's, Matt Scofield's and a tune by Scary Goldings with Josh Smith (I like guitar).  It all sounded pretty nice and my Mytek B+ displayed that the files fed by USB from Mini to B+ were CD quality? 

     

    Not sure how to find stuff on Amazon Music HD that is higher resolution than CD quality to test? 

     

    FWIW, the Mini is connected to the web by WiFi (Netgear hub is in next room, 6 ft linear from the Mini).

     

     

    No worries. Sample rate isn’t a decent indicator of bit perfect audio. You can take a CD quality WAV file and convert it to MP3. It will still be 16/44.1 but irreversibly damaged / lossy. 
     

    The Amazon interface shows stuff as HD and UHD but will only show sample rate once playback starts. 

    Share this comment


    Link to comment
    Share on other sites

    Wouldn’t it be nice if we could tell the difference by just listening and didn’t need some sort of visual confirmation?

    Share this comment


    Link to comment
    Share on other sites
    1 hour ago, MWDeBoard said:

    Wouldn’t it be nice if we could tell the difference by just listening and didn’t need some sort of visual confirmation?

    Of course one can tell the difference between good sound, great sound, and lousy sound.  No visual confirmation required.  But if you want to know if you are getting the best sound for a particular piece of music, you do need something more.  Chris's piece here is one aspect.  The Dynamic Range Database is another.  AS's ongoing Best Version Of series is a third.

    Share this comment


    Link to comment
    Share on other sites
    4 hours ago, firedog said:

    The issue is the Amazon app sends it to Windows mixer where it gets altered. If you set your Windows mixer to hi-res then it will stay in that sample rate. Still won't be bit perfect.

     

    Guess I don't understand sample rate versus bit perfect. Par for the course for me as I miss 80% of the tech talking here. 

     

     I use a Mac so where does Amazon app "send it" to get altered, iTunes?

     

    FWIW, the Amazon HD files sound better than MP3s, made the mistake of assuming that iTunes sold CD quality downloads years ago and bought an album (Gregg Allman's) and it sounded miserable. 

    Share this comment


    Link to comment
    Share on other sites
    46 minutes ago, 57gold said:

     

    Guess I don't understand sample rate versus bit perfect. Par for the course for me as I miss 80% of the tech talking here. 

     

     I use a Mac so where does Amazon app "send it" to get altered, iTunes?

     

    FWIW, the Amazon HD files sound better than MP3s, made the mistake of assuming that iTunes sold CD quality downloads years ago and bought an album (Gregg Allman's) and it sounded miserable. 

    Hey @57gold, you’re in the same boat as most people. Thanks for asking the questions/making the points. 
     

    Sample rate vs. bit perfect:

     

    Start with a CD quality file. It’s 16/44.1.  Play it without altering anything and it’s bit perfect at 16/44.1. 
     

    Using iTunes, turn down the volume 90% and it will still be 16/44.1, but no longer bit perfect because the digital volume control removes bits to reduce volume. 
     

    In this case it’s simple to hear the loss because it’s a massive volume reduction. All DACs and software that only show sample rate will still say 16/44.1, which doesn’t indicate the bits are no longer all present. 

    Share this comment


    Link to comment
    Share on other sites

    The non-bit-perfect investigation is interesting, but my question is, how does Amazon HD sound versus Tidal and Qobuz? 

    Share this comment


    Link to comment
    Share on other sites

    If only Amazon HD had Spotify's apps and algorithms!  For now I will stream lossy proudly.  I let my Amazon HD expire in favor of staying with the green and black.

    Share this comment


    Link to comment
    Share on other sites
    5 minutes ago, photonman said:

    If only Amazon HD had Spotify's apps and algorithms!  For now I will stream lossy proudly.  I let my Amazon HD expire in favor of staying with the green and black.

    Certainly nothing wrong with that. 

    Share this comment


    Link to comment
    Share on other sites
    12 hours ago, The Computer Audiophile said:

    Hey @57gold, you’re in the same boat as most people. Thanks for asking the questions/making the points. 
     

    Sample rate vs. bit perfect:

     

    Start with a CD quality file. It’s 16/44.1.  Play it without altering anything and it’s bit perfect at 16/44.1. 
     

    Using iTunes, turn down the volume 90% and it will still be 16/44.1, but no longer bit perfect because the digital volume control removes bits to reduce volume. 
     

    In this case it’s simple to hear the loss because it’s a massive volume reduction. All DACs and software that only show sample rate will still say 16/44.1, which doesn’t indicate the bits are no longer all present. 

     

    OK, may be a dumb question...but if the shoe fits!

     

    So, if I stream from Amazon HD on my Mini with both the app volume and iTunes volume maxed, and then use the analog attenuator on the B+ to modulate volume, do I have bit perfect play back from Amazon HD?

    Share this comment


    Link to comment
    Share on other sites
    33 minutes ago, 57gold said:

     

    OK, may be a dumb question...but if the shoe fits!

     

    So, if I stream from Amazon HD on my Mini with both the app volume and iTunes volume maxed, and then use the analog attenuator on the B+ to modulate volume, do I have bit perfect play back from Amazon HD?

    No. The apps for Windows and macOS are incapable of bit perfect. 

    Share this comment


    Link to comment
    Share on other sites
    14 minutes ago, The Computer Audiophile said:

    No. The apps for Windows and macOS are incapable of bit perfect. 

     

    Their iOS app too...  for now.

     

    Whereas you can connect Tidal app + iPhone to an MQA DAC (with Apple Camera Adapter) and MQA will light up on the DAC. Bit perfect is only interrupted on iOS when you get a sound notification. But Do Not Disturb mode solves that.

     

    They introduced 'Exclusive Mode' in March this year so someone over there at Amazon Music HD is on the right track.

     

    But I can't believe they haven't fixed their apps to do bit perfect yet. Given the resources they would have.

    Share this comment


    Link to comment
    Share on other sites



    Create an account or sign in to comment

    You need to be a member in order to leave a comment

    Create an account

    Sign up for a new account in our community. It's easy!

    Register a new account

    Sign in

    Already have an account? Sign in here.

    Sign In Now



×
×
  • Create New...