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24/192 Music Downloads Are Very Silly Indeed (2012)

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Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#81
the devil is in the DAC and ADC. You just can't turn 16bit/24bit data directly to/from analog without much loss. The 1/65536 accuracy voltage divider simply don't exist.

So, you have to up-sample the songs to high rates with less bits, like 1bit to 6bits, then do the conversion, and get the best SNR you can.

In this sense, there's simply a lot of advantage of using 24/196 since the above conversion can result in less loss and higher SNR

Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#82
post #18

I've said it before, this video demo is one of the very best I've ever seen. https://xiph.org/video/vid2.shtml So well prepared, so well presented, so little that could be removed without ruining it. I aspire to do such good demos but always fall so short.

> this video demo is one of the very best I've ever seen

I have said the same thing. I was a film major, a video producer, and a tech writer (now a programmer), and I am in awe.

Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#83
What about for non-humans?

Consider a dog that lives with a musician who plays, for example, trumpet. The musician plays the trumpet at home to practice, and also records his practices to review.

A trumpet produces significant acoustic energy out to about 100 KHz [1]. When the musician plays live the dog hears a rich musical instrument. When the musician plays back his recordings, half the frequency range that the dog could hear in the live trumpet will be gone. I'd imagine that this makes the recorded trumpet a lot less aesthetically pleasing to the poor dog.

[1] https://www.cco.caltech.edu/~boyk/spectra/spectra.htm

Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#84
post #48
post #9

I've always been able to tell when something on Spotify I've heard before is lower quality now. I can instinctively tell in my car when that's the case. It's mostly due to how loud certain parts of the song are or how it sounds at higher volumes. I guess, given what he says, that wouldn't be the case if made sure they were the same dB.

It is well known that music media for "popular" consumption are often intentionally mastered with much less dynamic. This is called "compression", but has, on the surface, nothing to do with compression of bits* . It's the dynamic that's compressed, making quieter and louder sounds be closer together. For markets with people that are more likely to care about sound quality, though, a much larger dynamic range is pres…

It's true that much popular music is heavily compressed, but you normally wouldn't encounter two differently-compressed masters of the same song. Two exceptions would be radio (some stations used to apply their own compression, and perhaps they still do) and some high-quality releases aimed at audiophiles that are produced from a less-compressed master. I wouldn't think that streaming services like Spotify would re-compress songs.

Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#85
post #74

Off topic, but I've noticed in the gym, sometimes the music playing from the instructor's iPhone through one of those cheap Ion Block Rocker bluetooth speakers (big boxy one, looks like a guitar amp) has very very noticeable pitch sag in various parts of various songs. It's via bluetooth, and the source is Pandora. I even googled Pandora and pitch change, and found some forums with folks discussing bluetooth causing…

At my greatest aspiration, I'm no more than a casual music listener - however I am very conscious of pitch. On more than one occasion, I've noticed that a song I'm familiar with seems off pitch, as in lower or higher key than I think of it in my head - and I seem to notice that particularly around shitty speakers or bluetooth or some combination of the two. Glad to know I'm not crazy :)

To your point, I would lean towards bluetooth as I've never associated the phenomena with Pandora. My friends and I mostly use Spotify.

Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#86
post #83

What about for non-humans? Consider a dog that lives with a musician who plays, for example, trumpet. The musician plays the trumpet at home to practice, and also records his practices to review. A trumpet produces significant acoustic energy out to about 100 KHz [1]. When the musician plays live the dog hears a rich musical instrument. When the musician plays back his recordings, half the frequency range that the do…

In my experience as a long time trumpet playing dog owner, the dog is generally thrilled when there is less richness in the noise, and generally less trumpet playing period. I say this with experience owning many dogs and having played the trumpet in a range from really badly and inexpertly, to pretty good... they don't care. Trumpets in person are just way too loud and a bit too much in general for most dogs.

Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#87
post #18

I've said it before, this video demo is one of the very best I've ever seen. https://xiph.org/video/vid2.shtml So well prepared, so well presented, so little that could be removed without ruining it. I aspire to do such good demos but always fall so short.

That is fantastic. The presenter manages to pull of "charismatic engineer" really well.

Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#88
post #78

Earlier quoted context omitted.

24/192 can capture audio well beyond what we can hear. These sounds can, though, lead to distortion that is within our hearing range, depending on the equipment used. Therefore, rather than just being useless extra data, it can be actively harmful to the listening experience.

But weren't those "outside our hearing range sounds that can distort our hearing range" present in real life when the recording was made? So I would have heard the distortions had I been there in real life?

The problem is that your speakers were not designed to reproduce sounds at those frequencies, so instead of faithfully reproducing those sounds (that you can't hear anyway) they may emit unintended artifacts/distortion (that you can hear).

Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#89
post #83

What about for non-humans? Consider a dog that lives with a musician who plays, for example, trumpet. The musician plays the trumpet at home to practice, and also records his practices to review. A trumpet produces significant acoustic energy out to about 100 KHz [1]. When the musician plays live the dog hears a rich musical instrument. When the musician plays back his recordings, half the frequency range that the do…

How do we know that the trumpet still sounds harmonically pleasing above 20 kHz? It may sound nice to the human ear, and a horrible mess to anyone with ultrasonic hearing capabilities.

Have we asked the dogs?

Re: 24/192 Music Downloads Are Very Silly Indeed (2012)

#90
post #63
post #38

This article makes the same mistake that is done frequently with video. So, let’s look at a similar issue with video. Your display is likely only 720p, or 1080p, but a 4K video on youtube will still look a lot better, although technically it should have no visible difference. But the reality is, we don’t get uncompressed video, or uncompressed audio. We have a choice between audio or video compressed with lossy codec…

Suppose you have a 5 Mbps data budget, 1080p display, and 4k source material. You will get better quality by first downsampling the 4k to 1080p and then compressing and distributing the result. If you compress and distribute the 4k, followed by downsampling to display at 1080p, you cannot recover the color and/or motion information that was lost in order to fit all of those pixels into 5 Mbps. However, if you have a…

Of course your theory is quite sound, but I will point out that in practice most 4k streaming content uses an HEVC codec, while most 1080p streaming content uses an AVC codec, so you'll likely have much better results on your data budget with the 4k signal even if significantly downsampled to your display.
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