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YouTube audio quality – How good does it get? (2022)

audiomisc.co.uk

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Re: YouTube audio quality – How good does it get? (2022)

#31

Post by Retric »

dylan604 wrote: post #30
xipix wrote: post #17

Nice analysis, for 1x playback speed. If you're playing back at a different speed, for example, for music practice, YouTube audio is awful. Why doesn't this huge AV platform use a better audio time stretch algorithm?

Because this is such a niche use the number of users taking advantage of this "feature" would be so small as to not get anybody a promotion

Changing playback speed is a heavily used feature. They’ve also refined it several times, recently adding 0.05 speed increments not just 0.25.

Re: YouTube audio quality – How good does it get? (2022)

#32

Post by atoav »

A good way of hearing the gras grow is a null test.

Take unprocessed audio and process it. Then take both the processed and unprocessed audio and add them to your audio software (e.g. Audacity). Now flip the polarity of one of the audio signals.

This allows you to listen to the difference between the two signals and if there is nothing there, guess what, they are the same or the differences are so small that theg are inaudible.

This is a great way to anger people with expensive hifi gold cables, because what is true in the digital also works in the analog.

You only need to make sure both ajdio signals are at the same level (by minimizing the level of the difference).

Re: YouTube audio quality – How good does it get? (2022)

#33

Post by evo »

krick wrote: post #29

Why would it be 6.5 ms late? It's not much, but way larger than I'd expect. I never knew encoding might shift the audio track.

I imagine the lossy encoding process could use a bunch of stacked filters to cut away imperceptible frequencies, but filters in the general case are implemented by summing delayed copies of the input and can smear the output in the phase domain. (There’s a branch of filters that avoid this but require computing the introduced delay and shifting the output to compensate.)

It’s a noticeable problem in audio production if e.g. a filtered kick drum goes out of phase and sucks amplitude when mixed with the original.

Re: YouTube audio quality – How good does it get? (2022)

#34

Post by mrob »

lazka wrote: post #8

See "Why not use graphs / frequency analysis to compare codecs?" https://wiki.hydrogenaud.io/index.php?title=FAQ#:~:text=Why%... "I decided that analysis should focus on the higher, more conventional rates – 48k and 44k1" - opus is always 48khz, so that doesn't mean much.

This. Your ears are not an oscilloscope. Lossy audio codecs are designed to exploit two major weaknesses in human hearing:

1. Poor sensitivity in bass and treble. See:

https://en.wikipedia.org/wiki/Equal-loudness_contour

2. Limited ability to hear multiple sounds simultaneously, or almost simultaneously. See:

https://en.wikipedia.org/wiki/Auditory_masking

Bernhard Seeber has some videos on Youtube with demonstrations of auditory masking:

https://www.youtube.com/watch?v=R9UZnMsm9o8

https://www.youtube.com/watch?v=bU0_Kaj7cPk

The only fair way to evaluate lossy codecs is with double blind listening tests.

Re: YouTube audio quality – How good does it get? (2022)

#35

Post by grimgrin »

Retric wrote: post #31
dylan604 wrote: post #30

Earlier quoted context omitted.

Because this is such a niche use the number of users taking advantage of this "feature" would be so small as to not get anybody a promotion

Changing playback speed is a heavily used feature. They’ve also refined it several times, recently adding 0.05 speed increments not just 0.25.

took me a while to recognize you can long press on mobile yt to 2x, maybe even more than 2x but I ain’t figured out the finger incantation

Re: YouTube audio quality – How good does it get? (2022)

#36

Post by DevinShah »

evo wrote: post #33
krick wrote: post #29

Why would it be 6.5 ms late? It's not much, but way larger than I'd expect. I never knew encoding might shift the audio track.

I imagine the lossy encoding process could use a bunch of stacked filters to cut away imperceptible frequencies, but filters in the general case are implemented by summing delayed copies of the input and can smear the output in the phase domain. (There’s a branch of filters that avoid this but require computing the introduced delay and shifting the output to compensate.) It’s a noticeable problem in audio production…

Is it possible to run the recorded input through the filters twice, doing the second pass in reverse to cancel out the phase shift?

Re: YouTube audio quality – How good does it get? (2022)

#37

Post by phonon »

xipix wrote: post #17

Nice analysis, for 1x playback speed. If you're playing back at a different speed, for example, for music practice, YouTube audio is awful. Why doesn't this huge AV platform use a better audio time stretch algorithm?

I think time stretching is done natively by your browser, not by Youtube at all. I use https://github.com/igrigorik/videospeed on sites...allows any media to be stretched. Did you try another browser?

Re: YouTube audio quality – How good does it get? (2022)

#38

Post by jeffbee »

togetheragainor wrote: post #22

For music listening, the YouTube Music app has settings for higher audio quality under "Settings > Playback". According to their documentation, this is "Upper bound of 256kbps AAC & OPUS": https://support.google.com/youtubemusic/answer/9076559?hl=en... EDIT: FWIW, I'm a Premium member. I'm not sure if this is a standard feature.

The worse problem for YouTube Music is that some of the source material is not the same as what you may have on physical media. There are entire labels that provide worse or at least different materials than they published to record stores. And then there is remaster roulette. What am I going to hear if I press play on "Rumours": the original that was born perfect, or one of the half-dozen remasters that have been issued as the original engineer progressively loses his hearing?

Re: YouTube audio quality – How good does it get? (2022)

#39

Post by cogman10 »

jorvi wrote: post #15
londons_explore wrote: post #2

Youtube probably have stats on viewer-happyness vs bitrate. I would take a guess that a higher bitrate = longer loading times, and viewers care far more about an extra few second of buffering than they care about audio quality, especially when they don't have the original to compare to.

The audio data is miniscule compared to the video data, and the size of it is tied to the video quality level. And everything is streamed in chunks. It'd only amount to milliseconds of extra buffering.

Not as insignificant as you might imagine, especially if you are talking about surround sound audio.

With newer codecs, doing 4k with 2Mb/s isn't unheard of.

For audio, on the other hand, 32 or 64kbps per channel isn't unheard of.

Re: YouTube audio quality – How good does it get? (2022)

#40

Post by nemomarx »

jurmous wrote: post #18

I have YouTube premium and I have access to experimental features and coincidentally they offer one feature called audio in high quality. So they are working on improving it. Description: High-Quality Audio Available until February 22 With high-quality audio, you can listen to music on YouTube in the best audio quality. How it works: Watch an eligible music video on YouTube and enjoy the benefits of higher-quality au…

why only on mobile? very curious
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