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4K HDR BluRay V Streaming

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Peluvius

Peluvius

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Luckily, I got the Harry Potter 8-movie UHD collection at a good price, because talk about underwhelming. I think the UHD movie Atmos soundtracks are a bit better at not sounding like multiple mono channels, but picture-wise, until the last 2-3 movies, the transfers scarcely look 2K, let alone 4K HDR.

Some of the best-looking and sounding content that I've experienced to date has come from Apple's TV+

The Apple plus stuff sounds and looks excellent in general I agree. There is a few articles I read around Apples market strategy in the content space and technical excellence was a core principle, it was actually one of the reasons put forward initially for them to not enter the space (challenges around technical delivery and not being able to differentiate on that basis). Watching Apple + I think they have nailed it. Jobs original acquisition of Pixar was one of the first steps down that road for them.

I have also noticed a distinct lift in the quality of soundtracks of newer content on Netflix and Stan, I would not be surprised if this was in part due to Apple raising the bar.
 

DanInCanada

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Since nobody has answered your original question yet ...

Blu-ray (standard or UHD) supports a whole bunch of standards for audio, but at least one track must be "lossless." They can include an uncompressed (CD quality or higher) track at ~1mbit/s per channel, but almost nobody does except for a few mono tracks. Popular options are a Dolby "True HD" track (which uses the same Meridian compression format as Tidal's lossless IIRC) up to 18mbit/s, or DTS "HD Master Audio" up to 24 Mbit/s. High-res sample rates are allowed but not common, most tracks are [email protected]

Both Dolby and DTS found a way to shoehorn extra "object-based" surround effect tracks into those lossless systems, so the formats have a long life ahead of them as far as disc playback is concerned.

In the other side of the tracks...

Lower-bitrate streaming movies have been using the same AAC compression format as most music services (even for 5.1 tracks) until recently. it's probably cheaper to license and it sounded better at lower bitrates than the old Dolby compression did.

Dolby has captured the "premiere" streaming market by leveraging the popularity of the existing "Dolby Digital" (AC-3) 640kbit/s format (which has been ubiquitous since the '90s and is supported by broadcast standards) and extending it to a slightly higher bitrate. "Dolby Digital Plus" (E-AC3) goes up to 6 Mbit/s and supports lots of channels; you can also encode those channels with "object" metadata so stuff can fly around overhead on an Atmos system. (Activating the "Atmos" light on a TV or Soundbar is almost certainly the reason streaming companies are paying for EAC-3.)

Dolby Atmos "object coding" can also be rendered and sent directly as a binaural signal for headphones, which has made it popular with music streaming platforms. (They're usually not streaming 7.1.4 channels, they're sending two compressed channels that were "baked" for headphone surround at the studio. Not sure what Apple is doing with head tracking, but they're not sending you 18mbps to do it...)

To sum up:
Most streaming services heavily compress their audio streams compared to Blu-ray.

Blu-ray audio allows for ridiculous data rates, so you may not notice the quality difference.

Home theater surround sound systems can take advantage of the extra information capabilities in Atmos streaming audio the same way they can for BluRay Atmos tracks... But that assumes the studio is actually making an effort and not just faking it with lazy mixes repackaged to turn on a few lights on your brother's TV.

as with most things, the big difference is between good mixes and bad mixes, not between formats.
 

phoenixdogfan

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I have been reading through a few threads recently but cannot find any thread specifically comparing the difference between 4k HDR local BluRay playback against the commonly available streaming services. I am still buying BluRay disks because I notice a big difference in picture quality in particular and still a difference in most audio soundtracks (for movies made or re-mastered in the last 10 years or so).

I listen to Tidal and find it is the same to me as CD playback. I notice the difference between the master and standard HiFi streaming for some music (not all). Why can't the video streaming services deliver audio with the same quality as tidal in multichannel? Or do they and I am just imagining things?

I understand BluRay will deliver a 128Mbps stream to your media system (combined image and audio), Netflix around 17Mbps and Apple 40Mbps. So clearly there is a difference in the quantity of data being used to reproduce. I understand the audio delivery for streaming services is compressed as opposed to the HD master uncompressed audio delivery from dedicated players.

Netflix make the following claim in literature:
  • 5.1: From 192 kbps (good) up to 640 kbps (great/perceptually transparent)
  • Dolby Atmos: From 448 kbps up to 768 kbps (Dolby Atmos is available for members subscribed to the Premium plan)

My wife gets angry with me for still buying disks but I do intend to continue with this for as long as I notice a difference in the quality of replay. What are the facts here?

Do most of us here still buy disks or is streaming close enough in quality terms to make that a waste of money?
Netflix has many movies in Dolby Vision 4K, and most of the rest in HDR 10. It has Atmos streams in Dolby Digital+, rather than Dolby True HD. For me, the streaming services are so convenient as to outweigh any quality differences.

For Netflix Atmos movies, I send the bitstream Atmos soundtrack via eARC to my Smyth A16 Realizer, so I can listen to them in 24 channels over headphones. The Dolby Vision or HDR 10+ video is rendered by my LG C1.

I know it would be even better with the same material on a Blue Ray disk, but you can't even hardly rent them, and if you can, the rentals don't come with an Atmos soundtrack for the most part. And storing a bunch of disks, I would watch at most 2-3 in my life just seems like a giant PIA. Been there, done that, and I wanted the space back.

Guess I'm just the kind of person who if he ever won the lottery, would just rent that 250' yacht for the annual week long cruise because he wanted all the fun but none of the burdens of ownership.
 
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Peluvius

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To sum up:
Most streaming services heavily compress their audio streams compared to Blu-ray.

Blu-ray audio allows for ridiculous data rates, so you may not notice the quality difference.

Home theater surround sound systems can take advantage of the extra information capabilities in Atmos streaming audio the same way they can for BluRay Atmos tracks... But that assumes the studio is actually making an effort and not just faking it with lazy mixes repackaged to turn on a few lights on your brother's TV.

as with most things, the big difference is between good mixes and bad mixes, not between formats.

Interesting detail, thank you. Curious what you mean when you say "Blu-ray audio allows for ridiculous data rates, so you may not notice the quality difference."?

You can certainly tell when the studio has made an effort on the sound. As an aside my wife, who is generally entirely agnostic on the audio quality front is noticing this as well and has even made a comment here and there.


Netflix has many movies in Dolby Vision 4K, and most of the rest in HDR 10. It has Atmos streams in Dolby Digital+, rather than Dolby True HD. For me, the streaming services are so convenient as to outweigh any quality differences.

For Netflix Atmos movies, I send the bitstream Atmos soundtrack via eARC to my Smyth A16 Realizer, so I can listen to them in 24 channels over headphones. The Dolby Vision or HDR 10+ video is rendered by my LG C1.

I know it would be even better with the same material on a Blue Ray disk, but you can't even hardly rent them, and if you can, the rentals don't come with an Atmos soundtrack for the most part. And storing a bunch of disks, I would watch at most 2-3 in my life just seems like a giant PIA. Been there, done that, and I wanted the space back.

Guess I'm just the kind of person who if he ever won the lottery, would just rent that 250' yacht for the annual week long cruise because he wanted all the fun but none of the burdens of ownership.

The convenience is hard to argue with. I only go for a BluRay of a movie with an awesome soundtrack (like the new Batman movie) but even then watching it on Apple is still a blast. I have a few I dust off every few years and spin up but how long before all the disks are 8k or there is some other step change improvement.

I agree the best boat you can get is someone else's.....:)
 

DanInCanada

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Curious what you mean when you say "Blu-ray audio allows for ridiculous data rates, so you may not notice the quality difference."?
I just meant that the huge difference in file size doesn't reveal the difference in quality.
I haven't seen any tests of where the sweet spot is for "perceptually lossless" lossy compression, but it's got to be lower than 192kbps-per-stereo-pair average for most TV shows and movies. (Since there's a lot more silence and fewer giveaways than in music, and compression has come a long way since MP3...)
 
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Peluvius

Peluvius

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I just meant that the huge difference in file size doesn't reveal the difference in quality.
I haven't seen any tests of where the sweet spot is for "perceptually lossless" lossy compression, but it's got to be lower than 192kbps-per-stereo-pair average for most TV shows and movies. (Since there's a lot more silence and fewer giveaways than in music, and compression has come a long way since MP3...)

Understood. This is exactly the sort of information I was interested in exploring in this thread.

I would be really interested to get a better feel for the point where we hit diminishing returns. How many Kbs make a difference to someone interested in audio quality with a decent setup? Word on the street is that Tidal master is around 1850 kbps using MQA with a max. sample rate of 352 kHz and I can hear the difference between that and the standard service which is 176 kbps so I guess somewhere between those two....:facepalm:

Aside from the endless hours of entertainment I have had from this site (I enjoy reading while I listen to music), the information here has also re-enforced the importance (to me) of not constantly buying stuff that makes no difference to what I can actually hear, and made it easier to do that without buying it and trying it....
 
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