Amazon launches lossless high-res music service!

[Bernard23]

Evidence? So far, my research pointed to all resampling being done in the AMHD app itself, bypassing the OS. Cannot prove this yet, however.

24bit/48kHz resolution is definitely Hi-Res. Do not see your point here.

Evidence? As far as I know MS W10 uses the most advanced and precise resampling algorithms (64-bit floating point.

Disclaimer: Personally, I do not use any Windows OS or software myself. But I like this forum because it is based on science not gossip.

Easy to prove, even without a DAC that displays sampling rate. Mine does, and AHD plays at whatever the default windows settings are (everything in Windows shared mode is default resampled to 24/48 whatever the original file is, unless you manually change the settings, you're not familiar with Windows so you'll have to this on trust, but it's pretty basic stuff tbh). Even if your DAC does not display sample rates, then easy to verify if Windows is working in exclusive mode, which it should do if you want it to automatically stream native file rates and avoid the up / down resampling. Just try playing another audi file whilst streaming from the amazon app, if you can hear it, then Windows is not configured for exclusive output. J River and tidal when set to exclusive mode (either using an asio or wasapi output driver) prevent this from happening.
The connection you fail to make is automatically streaming native file resolution is impossible in Windows in shared mode. The amazon app only operates in shared mode, despite having an exclusive mode toggle in the settings.
Happy to take pics, video etc but frankly it's really easy to test yourself, whatever your OS, though I suspect it's a windows config issue.

 

[Bernard23]

I should add that even if W10 has a great resample process, why do you need it? Ideally you bypass any unneccesary processing and stream from the media player straight to the DAC. There is no need to go through any additional processing unless you want to hear the Windows notification sounds, or mix other audio. I don't wish for either!
Plenty of interesting stuff about bit perfect streaming and the Windows kernel mixer in the J River forums, and a good amount isn't just gossip.

 

[Bamyasi]

Easy to prove, even without a DAC that displays sampling rate. Mine does, and AHD plays at whatever the default windows settings are (everything in Windows shared mode is default resampled to 24/48 whatever the original file is, unless you manually change the settings, you're not familiar with Windows so you'll have to this on trust, but it's pretty basic stuff tbh).

This does not prove resampling is done in Windows. Yes there is resampling involved and AMHD playback is not bit-perfect, that is correct. But how it works, AMHD app reads the system capabilities using system API (from your W10 audio settings in this case) and then it sets its internal resampling rate based on that. This way, Windows audio stack does not resample because digital output stream from AMHD app is resampled already and matches current OS settings.

Even if your DAC does not display sample rates, then easy to verify if Windows is working in exclusive mode, which it should do if you want it to automatically stream native file rates and avoid the up / down resampling.

Exclusive mode has nothing to do with automatic sampling rate selection. Exclusive mode allows application to implement sampling rate switching but it is not a requirement. It's the decision of application developers how they want to deal with the digital playback streams in different formats.

Just try playing another audi file whilst streaming from the amazon app, if you can hear it, then Windows is not configured for exclusive output. J River and tidal when set to exclusive mode (either using an asio or wasapi output driver) prevent this from happening.

I know TIDAL app implements if differently, that was not my point.

...automatically streaming native file resolution is impossible in Windows in shared mode.

True.

The amazon app only operates in shared mode, despite having an exclusive mode toggle in the settings.

Try playing any other sound when AMHD exclusive mode is enabled and you will see it is not allowed. That's exclusive mode. Automatic sampling rate switching is not part of exclusive mode API (although it obviously cannot be implemented in shared mode). Bit-perfect playback is not guaranteed in exclusive mode either; only made possible.

Happy to take pics, video etc but frankly it's really easy to test yourself, whatever your OS, though I suspect it's a windows config issue.

I suggest you do some more research on the net or experiment with your setup since your idea of how it works is not exactly correct.

 

[Helicopter]

A week or so into my trial period with Amazon HD, I have occasionally heard loud bursts of scratchy-sounding noise, sometimes when switching tracks in the same album, and sometimes at unpredictable points within a track. It's pretty unpleasant when it happens.... Has anyone else encountered this? I wondered if the problem is with the usb cable linking my laptop to an Oppo BDP-105 running in USB DAC mode, but this never happened with Tidal. Switching cables did not eliminate the problem. (I use Exclusive Mode, if that matters.) Thanks for your thoughts.

I have experienced this with Amazon music HD going from Echo Link into Schiit Modius. I figured the samples were incompatible for some reason. That track won't work right until the next day, but switch tracks and it is better right away.

 

[Bernard23]

This does not prove resampling is done in Windows. Yes there is resampling involved and AMHD playback is not bit-perfect, that is correct. But how it works, AMHD app reads the system capabilities using system API (from your W10 audio settings in this case) and then it sets its internal resampling rate based on that. This way, Windows audio stack does not resample because digital output stream from AMHD app is resampled already and matches current OS settings.

Exclusive mode has nothing to do with automatic sampling rate selection. Exclusive mode allows application to implement sampling rate switching but it is not a requirement. It's the decision of application developers how they want to deal with the digital playback streams in different formats.

I know TIDAL app implements if differently, that was not my point.

True.

Try playing any other sound when AMHD exclusive mode is enabled and you will see it is not allowed. That's exclusive mode. Automatic sampling rate switching is not part of exclusive mode API (although it obviously cannot be implemented in shared mode). Bit-perfect playback is not guaranteed in exclusive mode either; only made possible.

I suggest you do some more research on the net or experiment with your setup since your idea of how it works is not exactly correct.

Thanks for the lesson, and yes I'm aware that there are implementations with different media players that I don't fully understand, and I'm mostly concluding from my own observations.
So a couple of questions, why does AHD app resample prior to streaming? Why analyse system capability (which is capable of streaming 24/192 in my pc). If this is the case, why not stream at the native resolution, and make use of WASAPI that MS wrote specifically to bypass it's own mixer for exactly this type of application? If you are correct and the app is making a system capability assessment, then it's a pretty crap implementation, because it's not working. Every other media player I have tried on my system switches to native resolution using WASAPI event output settings.

Also, when AHD is set to exclusive mode, I think I already stated I can still hear Windows notification sounds when streaming AHD, I can still play other media sounds simultaneously, that's not exclusive mode. Try the same in tidal or musicbee or J River and it won't work, so they are working in exclusive mode. I see on two different devices, one running W7 64, the other W10 64.
I also noticed that every track was streaming to my dac (marantz HD DAC1) at 48k, (don't know bit depth, can't see that.), which just happens to be the Windows default shared output sample rate. When I changed the default shared output sample rate in the W10 sound settings, the rate shown on the dac was the same.
It seems reasonable to conclude that the actual sample rate used in the final conversion ie that I hear is that which is displayed on my DAC. Unless I manually changed the windows settings, every single track in AHD was streamed into the dac at the same rate, so wasn't actually hi res audio, and could not be bit perfect.

For whatever reason, it wasn't behaving as I'd expected (on my two devices) so I wasn't prepared to continue the sub. It's not isolated, there is a whole thread somewhere dedicated to finding a way to stream the native resolution from the app, but I can't remember where it is, which prompted me to look at in more detail in the first place.

EDIT - some links to discussion threads highlighting same issue, at best it's mixed, some systems are working properly, some not..it's already covered in an ASR thread.

https://www.audiosciencereview.com/forum/index.php?threads/amazon-music-hd.9415/

https://forums.stevehoffman.tv/threads/amazon-music-hd-unable-to-play-ultrahd.881405/

https://audiophilestyle.com/ca/bits-and-bytes/amazon-music-hd-is-still-lossy-r953/

https://www.amazonforum.com/s/quest...mazon-music-hd-important-exclusive-mode-issue

 

[Bamyasi]

Thanks for the lesson, and yes I'm aware that there are implementations with different media players that I don't fully understand, and I'm mostly concluding from my own observations.
So a couple of questions, why does AHD app resample prior to streaming?

Well, you need to ask Amazon developers

AMHD app is made available on four major platforms (MS Windows, macOS, iOS, Android) and across several different versions. From what I can see, Amazon developers are using a unified codebase for all platforms, unlike TIDAL, Qobuz or Spotify, who have their own unique application developed for each supported platform. Obviously, it is way much easier to maintain unified codebase for a portable application but it also limits capabilities on each platform, because you are forced to use lowest common denominator, sort of. You cannot add advanced feature easily on one platform unless it is also supported on all platforms. Now, media playback / audio stack on all those platforms is a mess -- buggy and limited functionality but also implemented differently on each platform. If I was developing portable audio playback code I would indeed try to stay away from OS-specific implementations as much as possible and code it in my own software instead. Considering bit-perfect playback was never a priority for Amazon (doubt their developers knew what it it) it is no surprise they tried the same approach.

Why analyse system capability (which is capable of streaming 24/192 in my pc). If this is the case, why not stream at the native resolution, and make use of WASAPI that MS wrote specifically to bypass it's own mixer for exactly this type of application?

Because they also need to be able to support streaming on macOS, iOS, Android (half a dozen different versions) and Fire OS (patched Android, also four or five versions in circulation).

If you are correct and the app is making a system capability assessment, then it's a pretty crap implementation, because it's not working. Every other media player I have tried on my system switches to native resolution using WASAPI event output settings.

Correction: every other Windows media player. AMHD app actually works as designed, they simply care less about 0.001% of hardcore audiophiles who cringe when thinking about non-bitperfect streaming.

Also, when AHD is set to exclusive mode, I think I already stated I can still hear Windows notification sounds when streaming AHD, I can still play other media sounds simultaneously, that's not exclusive mode. Try the same in tidal or musicbee or J River and it won't work, so they are working in exclusive mode. I see on two different devices, one running W7 64, the other W10 64.

I don't know, I am not a Windows expert as I said. My Lenovo laptop with W10 64-bit installed on it would not play back any other sounds when Exclusive mode is checked in AMHD. Just checked and confirmed it after updating to the lates AMHD app version to be sure, no way. Even if I pause AMHD playback (in Exclusive mode) and then try playing some YouTube videos in Firefox they will just roll on in silence. Note, AMHD Exclusive mode setting does not stick, so you need to check it every time you restart playback. Pretty annoying, let's hope they will fix it soon.

I also noticed that every track was streaming to my dac (marantz HD DAC1) at 48k, (don't know bit depth, can't see that.), which just happens to be the Windows default shared output sample rate. When I changed the default shared output sample rate in the W10 sound settings, the rate shown on the dac was the same.

I assume you are referring to Settings->System->Sound->Device properties->Additional device properties->Advanced tab->Default format? This setting is effective in both exclusive and shared modes. It is just a default audio format, application can choose to use it or not. AMHD seems to query and use this setting under W10.

It seems reasonable to conclude that the actual sample rate used in the final conversion ie that I hear is that which is displayed on my DAC. Unless I manually changed the windows settings, every single track in AHD was streamed into the dac at the same rate, so wasn't actually hi res audio, and could not be bit perfect.

It is a Hi-Res audio (unless you have selected 16bit/44.1kHz as your Default Format) but it is not bit-perfect, the latter is correct.

For whatever reason, it wasn't behaving as I'd expected (on my two devices) so I wasn't prepared to continue the sub. It's not isolated, there is a whole thread somewhere dedicated to finding a way to stream the native resolution from the app, but I can't remember where it is, which prompted me to look at in more detail in the first place.

I cannot agree more, it is very frustrating, especially considering Amazon's own hardware does not support AMHD streaming in UHD and there is strong suspicion that even HD playback (which is supported on some Amazon devices) is not bit-perfect.

 

[Bernard23]

I don't know, I am not a Windows expert as I said. My Lenovo laptop with W10 64-bit installed on it would not play back any other sounds when Exclusive mode is checked in AMHD. Just checked and confirmed it after updating to the lates AMHD app version to be sure, no way. Even if I pause AMHD playback (in Exclusive mode) and then try playing some YouTube videos in Firefox they will just roll on in silence. Note, AMHD Exclusive mode setting does not stick, so you need to check it every time you restart playback. Pretty annoying, let's hope they will fix it soon.

That is odd that it works for one device, but not another! I tried this test several times, after uninstalling and reinstalling the app, same result. One thing I could not test is the rate at which it streams on a mobile device, in my case Android, but since I use the built in dac on my phone, even with the LG so called quad dac, I'm not convinced of the value of paying extra for hi res audio.

I assume you are referring to Settings->System->Sound->Device properties->Additional device properties->Advanced tab->Default format?

Yes, exactly that, with the <allow device exclusive use> tickbox checked.

 

[StevenEleven]

I got the new Chromecast with Google TV in the mail. Google offered it to me for the low low price of free, so I ordered it, and I received it a few days ago.

Of course I am mindful of the digital age adage, whenever someone gives you something for free on the Internet, you are the product!

Anyway, the good news: It has a TV remote (unlIke prior chromecasts) and has a native Amazon HD app that streams up to 16-bit 48 kHz (that is CD quality or a shade better just in case you are a freak and can hear up to 24 kHz or so). I split the audio off from HDMI by optical out from my TV, through my Behringer DEQ2496 for a little room correction, and into to my receiver via optical. Yes I use the $3 DAC chip in my receiver. ; )

Also I can stream using Qobuz using the iOS app via chromecast from my iPad. I set the streaming quality in Qobuz to 16/44.1. The TV remote for the newfangled chromecast makes streaming from the iOS app to the chromecast much more enjoyable and the presentation on the TV screen is pretty nice even though there is no native Qobuz app for the chromecast. Qobuz confirms on the screen I am running lossless. Again I can split off the digital CD-quality audio signal via optical from my TV and into my audio gear.

There‘s also a native Spotify app for the chromecast with Google TV. And of course a native Youtube Music app. Both lossy streaming of course.

FWIW, & etc. It’s pretty nice if you are a music streamer via your A/V setup. Happy holidays to all!!

 

[f1shb0n3]

FYI - Fire TV cube at $99 currently is the cheapest and easiest way to stream Amazon Music HD at Ultra HD quality up to 24/192 for home setup with TV and AV receiver.
Some notes:
- Disable the Dolby Processing option in the FireTV audio settings to get 2 channel stereo output through HDMI. Otherwise it up-converts to multichannel which then the receiver down-converts to stereo when in stereo mode and the result is a mess.
- Ultra HD is disabled by default, you can enable with a checkbox in the Amazon Music app settings. It allows for one button click turning on and off of Ultra HD quality which is nice if you want to A/B compare even in a sort of blind way. I don't think I can distinguish it reliably though, curious if any of you can.

Wish Amazon Music add a feature like Spotify Connect to make the setup ideal. Probably they will someday.

 

[valerianf]

Yesterday there was an Amazon stick firmware update that reset all the parameters of my Amazon music HD setting.
When I lauched my first track the AVR received a 2.0 192 kHz format.
It is real HD with a very cheap hardware (the latest 4k stick).
But I prefer using the DD+ setting that allows the AVR dsp treatments.

 

[StevenEleven]

Thanks to @valerianf and @f1shb0n3 for your insights!

As it so happened, I received an Amazon Fire TV Cube from the family for Christmas. I followed your tips (directly above, which seem to apply equally to the Fire Stick 4K and the Fire TV Cube) and after a few app and system updates am enjoying an extremely convenient “Ultra HD“ stream over my A/V system right now.

And there is the icon in the top right of the app menu Home screen that I can use as an on/off switch to the default of knocking everything back to no more than a 16/48 stream if I want.

I know intellectually that this is perhaps utterly pointless and there is scant chance of any difference in audible sound quality, but hey, whatever, it’s kind of fun somehow.

As noted, you can alternatively set up the Fire TV to give you a DD+ stream—then the max rate is 16/48 it seems, but with a DD+ stream the full selection of Dolby Digital DSP features are accessible from my receiver. So lots to play with here.

 

[Bamyasi]

Yesterday there was an Amazon stick firmware update that reset all the parameters of my Amazon music HD setting.
When I lauched my first track the AVR received a 2.0 192 kHz format.
It is real HD with a very cheap hardware (the latest 4k stick).
But I prefer using the DD+ setting that allows the AVR dsp treatments.

I assume it is still upsampling everything to 192 kHz fixed rate? I am getting my FireTV 4K stick on New Year's Eve, so soon will be able to experiment myself but will be nice to learn about your experience as well.

 

[valerianf]

I made some tests using the Firestick 4k with various music: sampling rate is fixed at 192 kHz.
Compare to DD+ with a 48 kHz sampling rate i do not hear a big difference.
It seem to me that the DD+ encoding has stronger bass frequencies as in the real word.
The 192 kHz soundtrack seems too dry with very light bass.
May be somebody can confirm this remark, as it could be resulting from my equipments.

 

[StevenEleven]

I made some tests using the Firestick 4k with various music: sampling rate is fixed at 192 kHz.
Compare to DD+ with a 48 kHz sampling rate i do not hear a big difference.
It seem to me that the DD+ encoding has stronger bass frequencies as in the real word.
The 192 kHz soundtrack seems too dry with very light bass.
May be somebody can confirm this remark, as it could be resulting from my equipments.

I had the same impression, and when messing with REW for hours on end a while back I did some measurements with and without Dolby Digital surround and upmixing playback. Although things got very very confusing at times, REW consistently showed more bass for Dolby digital from maybe 70 or 80 hz on down, IIRC. DTS surround upmixing had less bass. Unprocessed stereo (still with subwoofer) had the least bass.

There are so many variables when messing with this stuff, I don’t know if these results would hold in all cases for all content. But there’s one unvalidated data point for you, FWIW.

 

[valerianf]

I think there is really an important difference between the two modes.
I used only two large tower speakers with a Yamaha AVR in "Pure direct".
That way there is only the format decoding (2.0), no DSP or sound correction engaged.
To me the 192 kHz soundtrack as an abnormal low level of bass.

For normal listening I am using DD+ with DSP up-mixing to 5.0
The result is amazing as it convinced me to listen music again after a 10 years gap.
At least the pandemic brought me the music back at home.

 

[Bamyasi]

I made some tests using the Firestick 4k with various music: sampling rate is fixed at 192 kHz.
Compare to DD+ with a 48 kHz sampling rate i do not hear a big difference.
It seem to me that the DD+ encoding has stronger bass frequencies as in the real word.
The 192 kHz soundtrack seems too dry with very light bass.
May be somebody can confirm this remark, as it could be resulting from my equipments.

No luck here. I've got my FTV Stick 4K delivered tonight, spent two hours downloading and installing update after update on it. There were probably 5 or 6 updates total, arriving one by one. After all things have settled, updated Amazon Music HD app on the stick would indeed show the correct device capability and matching playback track info. For instance, for an UltraHD 24/192 track: track quality, device cabability, and currently playing at are all listed as 24/192, so far so good. But my DAC still shows the actual audio it receives has sampling rate fixed at 24/48, no matter what. It would never receive anything but 24/48, even after trying all combinations of the FTV 4K system sound settings. Maybe it's my HDMI extractor issue, I am not sure, I do not have an AVR to test it. However, I have bought this particular extractor model because its Amazon page claims it supports up to 192 kHz audio. Tried both Toslink optical and S/PDF output but no difference.

 

[valerianf]

About the Firestick 4K there are two settings to adjust:
In the stick audio menu you need to select stereo 2.0
In the Amazon Music app you need to select HD.
I read 192 kHz only after the latest firmware update of the stick, but I may not have noticed it before.
It may also be the hdmi handshake with your device that could limit the sampling rate.

 

[nikky]

As for me, Amazon Music can satisfy almost all daily listening needs, while Tidal is more for people who take audio quality seriously. If you have an Amazon Prime membership, you can enjoy over 2 million songs for free and no ads. Prime members can also upgrade to Amazon Music Unlimited with subsidization. Well, you can save a batch of money with Amazon Prime. I'd like to download Amazon music to my mp3 player so that I can listen to them while running in the morning. Since my mp3 player is not supported, I get a tool Tunelf Amatune Music Converter, which currently works very well.

 

[AdamG]

As for me, Amazon Music can satisfy almost all daily listening needs, while Tidal is more for people who take audio quality seriously. If you have an Amazon Prime membership, you can enjoy over 2 million songs for free and no ads. Prime members can also upgrade to Amazon Music Unlimited with subsidization. Well, you can save a batch of money with Amazon Prime. I'd like to download Amazon music to my mp3 player so that I can listen to them while running in the morning. Since my mp3 player is not supported, I get a tool Tunelf Amatune Music Converter, which currently works very well.

Welcome Aboard @nikky.

 

[SIY]

As for me, Amazon Music can satisfy almost all daily listening needs, while Tidal is more for people who take audio quality seriously. If you have an Amazon Prime membership, you can enjoy over 2 million songs for free and no ads. Prime members can also upgrade to Amazon Music Unlimited with subsidization. Well, you can save a batch of money with Amazon Prime. I'd like to download Amazon music to my mp3 player so that I can listen to them while running in the morning. Since my mp3 player is not supported, I get a tool Tunelf Amatune Music Converter, which currently works very well.

The HD version of Amazon Music makes no concessions regarding sound quality, it's all at least 16/44, with many available hi res options. And it's device-agnostic; my wife and I use it in the three sound systems in the house, on my iPhone when out hiking, and in her car when she's doing cross country trips.