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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)

#151

Post by arrrvalue »

romwell wrote: post #148
arrrvalue wrote: post #138

and yet, we are nowhere near being able to electronically reproduce a live acoustic music performance. have you ever walked by a bunch of musical sound coming out of a room and thought to yourself, "wow, those live musicians sound great" only to discover it was just a stereo playing? nope. as engineers we will never solve this problem as long as the "44.1kHz is good enough" dogma is perpetuated. here's a question. wh…

>as engineers we will never solve this problem [reproduce a live acoustic music performance] as long as the "44.1kHz is good enough" dogma is perpetuated It's the opposite. We are never going to solve this problem if we are going to focus on things that have nothing to do with the problem. Compare and contrast: >as engineers we will never solve this problem as long as the "copper wires are good enough" dogma is perpe…

interesting viewpoint, however, did you think about the experiment I presented? without an answer, sample rate and cabling cannot be considered equivalent distractions on the road to high fidelity.

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

#152

Post by kazinator »

Florin_Andrei wrote: post #89
tzs wrote: 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?

If we boost the frequencies even in just the range 10-20 kHz, things sound harsh and fizzy to the human ear.

The frequencies there are no longer musical in the sense of being recognized as musical notes.

That is to say, although in a pure arithmetic sense, frequency 148080 is an A, since it is a power of two multiple of 440; five octaves above it, we don't hear it as an A tone.

The frequencies in that ballpark just have to be present to add a sense of "definition" or "crispness" or "air" to the sound.

In fact, this can be faked!

In the OPUS codec, there is something called SBC: spectral band compression. What this refers to is basically a hack whereby the upper harmonics of the signal are completely stripped away, and then re-synthesized on the other end based on a duplicate of the lower harmonics or something like that. The listener just hears the increased definition.

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

#153

Post by daurnimator »

zaroth wrote: post #143
Const-me wrote: post #134

If the only thing you do with your music is listen, then yes, 24/192 delivers questionable value compared to the more popular 16/44.1 or 16/48 formats. However, all musicians I know use these high-rez formats internally. The reason for that, when you apply audio effects, especially complex VST ones, these discretization artifacts noticeably decrease the result quality. Maybe, the musicians who distribute their music…

TFA specifically addresses this and agrees 100% with you on it. Develop in 24/192, but ship in 16/48. Good point about supporting better downstream remixing!

I feel like there is some parallel to open source and GPL type licenses: you can never know which of your customers may wish to remix or further work on your materials, so you should ship the "source" material.

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

#154

Post by nayuki »

flavio81 wrote: post #65

Good points in the article, but it has some flaws. The problem whenever somebody writes about digital audio, is that it is very tempting to hold on to sampling theory (Nyquist limit, etc) and totally discard the problems of implementing an actual Analog-Digital and Digital-Analog chain that works perfectly at 44100Hz sample rate. I agree with the assesment that 16 bit depth is good enough; even 14 bit is good enough…

I don't think there are flaws in the article as you claim. It already explicitly explains that oversampling at the ADC or DAC is an acceptable engineering solution:

> Oversampling is simple and clever. You may recall from my A Digital Media Primer for Geeks that high sampling rates provide a great deal more space between the highest frequency audio we care about (20kHz) and the Nyquist frequency (half the sampling rate). This allows for simpler, smoother, more reliable analog anti-aliasing filters, and thus higher fidelity. This extra space between 20kHz and the Nyquist frequency is essentially just spectral padding for the analog filter.

> That's only half the story. Because digital filters have few of the practical limitations of an analog filter, we can complete the anti-aliasing process with greater efficiency and precision digitally. The very high rate raw digital signal passes through a digital anti-aliasing filter, which has no trouble fitting a transition band into a tight space. After this further digital anti-aliasing, the extra padding samples are simply thrown away. Oversampled playback approximately works in reverse.

> This means we can use low rate 44.1kHz or 48kHz audio with all the fidelity benefits of 192kHz or higher sampling (smooth frequency response, low aliasing) and none of the drawbacks (ultrasonics that cause intermodulation distortion, wasted space). Nearly all of today's analog-to-digital converters (ADCs) and digital-to-analog converters (DACs) oversample at very high rates. Few people realize this is happening because it's completely automatic and hidden.

The main point of the article is to argue that storing or transmitting music above 16-bit, 48 kHz is wasteful and potentially harmful. It still fully condones using higher specs for audio capture, editing, and rendering.

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

#155

Post by kazinator »

tomc1985 wrote: post #3

While the extra quality is lost on listeners, from experience I've found that super-HQ source material can change your results (for the better) when fed through distortion/compression/warming effects processors

In the amplitude domain, you definitely need more bits for that type of processing, and many other types.

Digital distortion basically simulates high gain with soft clipping, which basically takes a narrow slice of the amplitude domain and magnifies it. The extra resolution has to be there for that not to turn into ugly sounding shit with artifacts.

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

#157

Post by sundvor »

jaquers wrote: post #102
RachelF wrote: post #69

To be replaced soon by "4k video is very silly indeed" If you look at the angular resolution of the eye, unless you are sitting very close to the screen, you can't resolve 4k video.

Can't tell if this is sarcasm or not, but I think that's sort of the point. You want a high enough pixel density so you can't perceive pixels at normal viewing distance, and I can definitely see pixels on my 42in 1080p screen from across the room.

I'm going to go for "sarcasm" there.

I use a 65" 4k TV with my HTPC in the living room, but often do desktop-ish things on it. (Logitech's wireless keyboards are great).

The difference in resolution between 1080 and 2160 is huge. 1080 is just fuzzy.

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

#158

Post by ddingus »

jahnu wrote: 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 amazingly well presented.

Agreed. Wow!

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

#159

Post by WalterSear »

kazinator wrote: post #147
Const-me wrote: post #134

If the only thing you do with your music is listen, then yes, 24/192 delivers questionable value compared to the more popular 16/44.1 or 16/48 formats. However, all musicians I know use these high-rez formats internally. The reason for that, when you apply audio effects, especially complex VST ones, these discretization artifacts noticeably decrease the result quality. Maybe, the musicians who distribute their music…

I do not believe it. 24 bits is definitely needed for processing (better yet, use floating-point). Not 192 kHz; no friggin' way. Repeated processing through multiple blocks at a given sample rate does not produce cumulative discretization problems in the time domain; it's just not how the math works.

Unless you are altering the time or pitch, which, these days, you are more than you are not.

But no, musicians aren't releasing things at ultra-resolutions because they expect others to reuse their work. The ones that are, are providing multitracks.

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

#160

Post by cornstalks »

rblatz wrote: post #131
jahnu wrote: 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.

Unfortunately this video doesn't work on iOS. I'll try to remember to watch this next time I'm at a computer.

It's available on YouTube[1] as well, which should work just about everywhere.

[1]: https://www.youtube.com/watch?v=cIQ9IXSUzuM

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