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24-bit/192kHz music downloads and why they make no sense (2012)

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Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#121
post #110

Earlier quoted context omitted.

As I responded below, you are confusing math with physical reality. A true 44.1 kHz converter can't realistically capture frequencies ~18-20 kHz due to the limitations of filters used in the process. A perfect lowpass brick-wall filter just does not exist - they all introduce artifacts, which a trained ear can identify. You don't need to be a dog to hear the difference, just someone who does not assume that Nyquist t…

Is there evidence that a trained ear can reliably perceive these artifacts in a blind test of converters? I'd be interested in reading those links since converters typically oversample into the mHz range. At 11.29 mHz (256x 44.1 mHz), Nyquist will be at 5.64 mHz. Even the cheapest consumer converters are performing this type of oversampling.

If you are looking for studies, this one comes to mind: https://www.researchgate.net/publication/289039184_The_audib...

A quick search returned this PDF with a nice diagram of what aliasing looks like: https://download.tek.com/document/76W_30631_0_HR_Letter.pdf

To draw a design parallel: pixel-perfect design isn't something we are born with, noticing tiny details is a developed skill.

And yes, you are on point: oversampling is used extensively, but this just points at the exact issue: Nyquist theorem gave us a math algorithm, we still need to account for the electronic component imperfections. And then we are entering a different space of quality/precision/psychoacoustics/perception/etc. Meaning, not all converters, not all pre-amps, not all mics "sound" the same, even when they use same types of components on paper.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#122
post #8

This really is driving a muscle/super car, or drinking expensive wine. At the end none of specs or tests matter. It is a form of art. If it makes the listener feel better (even if its just psychological) then its probably worth it.

Correct. I've paid for Tidal for a decade because I just like the peace of mind that it's closer to the original recording. I'm sure it's mostly placebo, but I like it.

The original recording of almost all music on Tidal was done with equipment that was very, very far from the 192kHz "fidelity" it claims.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#123

Music producer here. High resolution audio is useful for editing and anywhere there might be downstream processing or format conversion that may or may not be high quality, let alone lossless. The article covers that pretty well. However, the article claims that the final distribution doesn’t need to have a bit depth of more than 16. That does not match my experience. I can tell the difference between my renders that…

> I can tell the difference between my renders that are 16 bit vs 24 bit.

established using double blind testing, I assume?

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#124

I cannot hear the difference between 16/44.1 (and by extension, 16/48) and High-Res Content generally, be they HDCD, SACD, or just straight-up Masters from Qobuz. This is on multiple sets of equipment, ranging from El Cheapo earbuds all the way to HD800 cans and full-fledged tower speakers being bi-amped. That’s not why I go for High-Res stuff, though. It’s all about archival, at least for me. With a 24/192 Master in…

Decades ago, I was treated to an ABX test in my brother's recording studio. I easily recognized and preferred a 24/192 master he played versus the 16/44.1 down-mix. I honestly don't know whether there was something wrong with the down-mix, but qualitatively it did feel like it was "muffled" and coming from speakers, while the master really felt like live performance. He was surprised that I could tell them apart. I a…

This is an extremely hard comparison to do well. I'll give a few examples as to why:

Small differences in gain are ABX able much more readily than differences in noise at the 16 vs 24 bit level. So if the signal chain gives even a small difference in gain between the samples that's what you'll track. A reasonable conversion path to 16 bits for mastering will also apply dithering and some kind of brickwall limiting (you have to limit after the dither or as part of the dither as dither can change levels!), and this can result in gain changes. The DAC may behave differently or have outright bugs for some configurations too.

This is particularly true wrt reconstruction filters for sample rate differences. And if you were comparing 44.1k and 192k then the physical DAC itself was likely running at a different rate and its _analog_ filters are probably better optimized for one vs the other (this is less true for 48k vs 192k, as the hardware likely runs at the same rate for both). So one answer to this comparison can be "on this particular hardware this rate is better than that rate"-- but that's a implementation property not a property of format choice.

You might think, "okay I'll use a mathematically perfect down and up conversion process and run the DAC in the exact same configuration for all cases". But even then you run into issues like after reconstruction the _inter sample_ peak levels will be higher than the levels of the samples, so you have to handle that and in a way that doesn't produce a gain difference between the two configurations. (probably by running your perfect process and finding the gain level that results in no limiting, then making the gain of the original match).

And then for the high rate vs non-high rate you have to deal with the fact that most amplifiers are not particularly linear (compared to well constructed software at least!) and that any real speaker is very far from linear. This means that the presence or absence of ultrasonics will change the audio in the 0-20khz band.. Before you think "well that could be a reason that high rate is better" observe that if there was some consistently good effect from the ultrasonics you could just bake it into the low rate sample.

> but in my 50s I know

Yeah if you're in your 50's you're absolutely not hearing differences way up above 20khz (especially if you're male), I bet you can't even hear CRT flybacks from 100 yards anymore. :P Most people have no idea how much their high frequency hearing degrades as they age because it plays approximately no role in your life, but it's real, dramatic, and as far as I know happens to everyone.

I don't mean to discount your experience: I don't really doubt that it was real. But answering the general question of the necessity of low vs high rate probably takes a team of experts, armed with test gear and the designs of the HW/SW in question, to vet the test configuration. Testing a _particular_ configuration without the ability to distinguish its implementation quirks from format-fundamentals is much easier and that's what most attempts to test this question are actually testing.

By testing in a recording studio you were doing far better than most such comparisons. Usually people try comparing different files and they're comparing entirely different mastering processes. Files made for the "high res" market will often have much less compression and limiting then files made for commercial radio play / casual listening... and truly do sound obviously much better. Some of my favorite recordings are rips from vinyl. Vinyl is an awful format from the perspective of audio fidelity, but it's also pretty intolerant of excessive compression and limiting because the record will skip if the needle is bouncing off the rails. And more recently I suppose they also avoid over compression there because of the difference in target listener/environment.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#125

Music producer here. High resolution audio is useful for editing and anywhere there might be downstream processing or format conversion that may or may not be high quality, let alone lossless. The article covers that pretty well. However, the article claims that the final distribution doesn’t need to have a bit depth of more than 16. That does not match my experience. I can tell the difference between my renders that…

thermal noise allows about 18-22 bits of real precision at audio level voltages, so it's plausible that 16 bit is somewhat limiting

16 bit may limit it on the input side, but the question is more about human hearing's sensitivity on the "output" side ...

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#126

192 kHz vs 48 kHz can make a difference if you slow down the audio. If you pitch shift down 2 octaves, the ultrasonic range 20-80 kHz turns into 5-20 kHz and there will be large difference between 192 kHz and 48 kHz sources. However, I do not know if it would sound good because the mixing engineer cannot hear those frequencies and mix them properly, or the microphone might not catch it or some of the material could b…

[deleted]

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#127
post #50

Just get one of those "hi fi" valve amplifiers from Amazon you see under $100. The valve already distorts the sound, so you don't need to bother paying more for low distortion anywhere else in the audio chain. Saved you thousands of dollars, done!

Distortion is why people love the sound of vinyl.

And its all good! It's perfectly fine to say "I prefer the sound when the whole mix (or just that guitar) ends up being subject to interesting and possibly harmonically relevant distortion at low levels".

Just don't say "The version with the distortion is more accurate than the one without", because that's a lie.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#128

Earlier quoted context omitted.

It's just means you have a shitty audio tract with not enough shielding. Move to SPDIF/TOSLINK.

I have an external audio card, if I put it on a laptop I can hear the modem-like sounds. I wonder why it is so sensitive, should not DAC produce strong signal that cannot be easily affected by radio waves? Also my headphones are extremely sensitive. I can touch the ring and sleeve of a jack with a finger, and touch a metal bed frame with a tip and I hear quiet clicks as I move the tip along the metal. Sometimes I do…

the radio waves could be interfeering with the signal before it gets amplified

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#129
post #18

I'm curious if the audio was being sent bit-perfect to the DAC for all of these tests (ALSA direct), or if it was being run through the audio mixer and being resampled I can always tell if my 44.1 songs are being resampled to 48 because they're being run through the OS mixer

Proper audio resampling should not be identifiable. Of course, the OS mixer probably doesn't do proper (CPU expensive) resampling. But a quality audio player should account for this and do it's own.

If you're not on a US-based IP, you should check out https://src.infinitewave.ca/

It is an incredible resource to see the quality of the resampling algorithms used by the actual production software likely used in any digital audio workflow.

You will see that while the best are indeed almost 100% transparent, many are not.

Re: 24-bit/192kHz music downloads and why they make no sense (2012)

#130
post #108

Earlier quoted context omitted.

I might be something from the middle. Yes, I did spend a hefty 5000 euros to my headphone setup. And yes it sounds absolutely magical and every day I'm happy listening to music with it. But I also have a large multi-terabyte music collection, I follow new music, go to concerts, go to parties, talk about music with my friends in signal group chats. It's a hobby, and when you get a bit older and start having some savin…

When I got old enough to finally afford those toys I discovered I couldn't hear above 16khz anymore.

It is not only that. It's the spacing, how the bass sounds, separation of instruments. There's so many interesting headphones in the midrange to try out. Compare the Hifiman HE1000se to Heddphone 2 GT, or to Focal Clear MG and you'll understand.

Also with HEDD you get a handcrafted device made in Berlin. And if you go with nicer cables, they are very beautifully done and feel great. There is no difference in sound of course. Some people like jewelry, I can get similar enjoyment from beautiful audio equipment and cables.

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