Does anybody notice a difference between the "Best Quality" option (previously labeled Auto), and the Dolby Digital 5.1 option. I know that "Best Quality" normally sends PCM, but audibly does it sound better?
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Poor Dynamic Range - Even with Full enabled
- Thread starter Colonel Badger
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Does anybody notice a difference between the "Best Quality" option (previously labeled Auto), and the Dolby Digital 5.1 option. I know that "Best Quality" normally sends PCM, but audibly does it sound better?
In theory the DD option should sound worse, because the ATV4 apparently doesn't have a passthrough option but decodes all sound to PCM to be able to mute it when you use Siri. So when you set it to output DD, it just does another lossy encode which can only make the sound worse (whether the difference is actually audible is another question though). The only scenario I can think of where the DD option would make sense is if your playback system doesn't support multichannel PCM.
Doesn't best available just mean that stereo is selected for stereo soundtracks and DD 5.1 is selected for DD 5.1 soundtracks?
No. "Best" means it will decode, process, and send as PCM multichannel. The "Dolby Digital 5.1" option will decode, perform any processing if needed (for ex. "Reduce Loud Sounds") and then re-encode as Dolby Digital 5.1 before sending out to the AVR.
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No even when selecting DD 5.1 that's what happens if only a stereo track is available. Auto/Best Quality delivers a PCM stream that, in theory, is superior because the ATV doesn't have to re-encode in to DD 5.1 to deliver
PCM stream will deliver it better, but it's read by A/V Receivers channel by channel. The A/V receiver cannot (most so far) are unable to process PCM 5.1 and output it to PLX II 7.1 or DTS 7.1. So you have two dead rear speakers for people with 7.1 setups.
One think I've noticed is that Apple media is encoded at varying volume levels (or maybe formats). For example, watch the last trailer for "The Force Awakens" thru the trailer app - it's ear splitting loud at normal volume level and has great dynamic range. Then watch the same trailer thru the iTunes store - the volume is much lower and sounds thin even when I crank the volume.
TV shows seem to be encoded at a higher level than movies. Perhaps it just sounds that way because TV shows are in 5.1, and the movies may be in 7.1 and then incorrectly downsampled.
Still doesn't explain why the Showtime app is generally louder than the HBO Now app, but that's a different problem.
The VUDU app though my Sony Android TV sounds incredible (the on screen display says Dolby Digital Plus). I wish Apple would get the ATV to sound as good, because I much prefer the ATV interface.
TV shows seem to be encoded at a higher level than movies. Perhaps it just sounds that way because TV shows are in 5.1, and the movies may be in 7.1 and then incorrectly downsampled.
Still doesn't explain why the Showtime app is generally louder than the HBO Now app, but that's a different problem.
The VUDU app though my Sony Android TV sounds incredible (the on screen display says Dolby Digital Plus). I wish Apple would get the ATV to sound as good, because I much prefer the ATV interface.
Jeff, your description is spot on. The compression you mention in #2 is what led me to this thread. After four pages of posts, I was really hoping to stumble across a fix. Alas, it seems this is something that only Apple can address.
I've submitted feedback and a bug report to Apple. Crossing my fingers that they're listening to all of us and working on a fix for the next update.
Thanks. Yes, this is definitely something Apple needs to address. Unfortunately, despite submitting thoroughly detailed bug reports with example files and clear instructions for repro, Apple has largely cast aside my efforts, effectively claiming my workflow is somehow to fault. However, the specific responses I've received to my reports (one being quite hilarious) clearly indicate that the average Apple engineer is neither trained, nor has the equipment to properly respond to incidents regarding Dolby / surround sound. (I imagine a young 20-something sitting in a cubicle with an iMac cranking out bug replies to meet a daily quota of some sort.)
If enough customers make enough noise, maybe someday they'll assign a specialist to look after Apple TV sound issues. For now, I get the impression whomever was originally in charge of that aspect is currently off working on another project...
While I don't think this is always a good idea, perhaps reaching out to Tim Cook with a link to your bugs and your concerns may elevate the problem ?
Please. If you're interacting with Apple tech engineers who don't understand this problem, then something is seriously wrong. Other devices get this right but Apple clearly does not.
I still hear this issue. Is Apple ever going to fix this? I watched Jungle Book last night and the dynamic ranges was terrible compared to the same move on Vudu using the Roku.
I still hear it too, I was watching Star Wars, The Force Awakens, the other day and the dynamic range whilst not terrible is definitely worse than other sources.
I wonder if it will be fixed in tvOS 10.
IMHO, VUDU has much better sound quality than any other streaming service I've used (and I have almost all of them). The display says Dolby Digital Plus, which the Dolby webpage says is supported on iOS and tvOS. I wish Apple would use it, as their rentals sound too quiet and thin by comparison.
Rented "Zootopia" from iTunes tonight, and at one point stopped the movie to see if "Reduce Loud Sounds" had turned itself on because that's exactly what it sounded like. Each time the movie should have gotten louder, it felt like I had to reach for the remote and turn it up again (and was already listing at louder volume than we normally do for blu-rays).
Googled the problem after the movie and found this thread. So what's the deal; is Apple applying a compression filter when they encode the films for iTunes at the source or what?
Googled the problem after the movie and found this thread. So what's the deal; is Apple applying a compression filter when they encode the films for iTunes at the source or what?
I find no difference. I even shut off Siri hoping it was some sort of overlay. The audio on this thing is straight up compressed. Don't have this issue on other sources. It's almost as if it's in permanent nighttime mode.
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One can only hope. I was pretty amped when I started seeing DD+ in the Disney titles only to find it's not worth much.
This is exactly my experience with the ATV4 too. I usually end up setting the volume of my Pre-Pro 20 clicks more when streaming on the ATV4 compared to when streaming from my Sony Blu-ray player or from Chromecast 2. I very much prefer using the ATV4 because of the faster response and also because of the superior remote however it is very annoying to have to remember to adjust the volume whenever I switch sources.
I am hoping the new OS version will finally contain the fix to this issue/bug. I do suspect just like others that this issue is somewhat related to Siri voice and remote feedback sound integration. IMHO, Apple should provide an option for the users to be able to select bitstream (DD+ at the minimum) as opposed to just the Surround Sound (DD) and PCM output options. I'd rather forgo siri integration and remote sound feedback just to get proper surround and better dynamic range audio output.
It's been this way since before ATV4. I just figured it was a limitation of the device. Given the different ranges in sound quality between apps on the device, I believe it is a limitation of the iTunes files themselves, likely some form of compression. They need to step it up of this is the "future of television", because if it is, it sucks.
I'm not sure that's the case since a number of users have reported that the very same iTunes movies played back on ATV3 have better dynamic range. That's likely because the ATV3 sends the untouched bitstream to the receiver.
For what it's worth, when I play back my blu-ray movie rips from Plex on the Apple TV 4th generation, the dynamic range is not clipped the way it was in iTunes movie rentals; so I don't believe it's an issue with the device as a whole. Either iTunes as an app is stuck in "reduce loud noises" mode, or Apple's content at the source is being encoded with audibly compressed dynamic range.
I agree. I play DVD rips through Infuse and they playback with full dynamic range, probably because Infuse sends the bitstream. Even including DTS sound tracks. So the hardware is capable.
That hasn't been the case with us. There has always been a significant variance in dynamic range between ATV and the rest of the devices. If anything, its worse now.
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I would tend to agree its the source. The bizarre thing is the previews don't have a dynamic range issue. Its like they've added some sort of compression to the files themselves.