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There is no point to distributing music in 24-bit/192kHz format.

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Re: There is no point to distributing music in 24-bit/192kHz format.

#231

Post by kragen »

shasta wrote: post #77
cmer wrote: post #49

Earlier quoted context omitted.

Humans will hear the impact > 20kHz frequency has on the lower frequencies, not the 30kHz frequency itself. That's been proven a million times.

In other words, your theory is that the superposition principle doesn't hold for sound waves.

Well, the superposition principle only holds in linear media. Sound waves can propagate in linear media, but they can also propagate in nonlinear media, and any medium that can carry sound will go nonlinear at sufficiently high amplitudes.

Re: There is no point to distributing music in 24-bit/192kHz format.

#233

Post by nullc »

cop359 wrote: post #187
Anechoic wrote: post #99

Earlier quoted context omitted.

Agree one-hundred percent about the room (although the prescription isn't always as simple as "get a thicker rug" etc). The other issue regarding high-frequency sound reproduction is that in most cases, the loudspeaker won't be outputting much beyond 22-25 kHz (assuming very good quality loudspeakers, cheap consumer grade units might struggle to hit a -6 dB point at 18 kHz) and even for the speakers that have usable…

I don't really know much about this, but wouldn't the 22kHz sounds potentially create beats in the lower frequencies?

Acoustic "beat tones" aren't "real" tones— you hear them because of non-linearies in the ear-brain system, but you have to hear the initial tones first. (Well, unless you're talking >>130dB SPL levels where the air starts becoming non-linear, but then lower frequency recording would capture it fine)

If you could hear subharmonic beats from ultrasonics then it would be _very_ easy to demonstrate, alas.

Re: There is no point to distributing music in 24-bit/192kHz format.

#234

Post by nullc »

qq66 wrote: post #205
DanBC wrote: post #142

Earlier quoted context omitted.

Are they talking about "beat frequency" type effects?

Yes. A 40KHz tone and a 41KHz tone will interfere with each other and can create 1KHz tones that are audible. Edited to correct error, thanks anechoic.

They don't— the air is linear (except at insane sound pressures) so there is no interference. While the ear is not linear, it doesn't respond at those frequencies.

If it really worked that way it would be trivial to demonstrate. Alas, it doesn't.

Re: There is no point to distributing music in 24-bit/192kHz format.

#235

Post by nullc »

noonespecial wrote: post #73

I was under the impression that two inaudible high frequency tones could interfere with each other to create an audible interference pattern. (I think known as a "beat frequency"). If this is the case, then all of the arguments in the world about the maximum audible single frequency are irrelevant. Imagine music composed entirely of these beat frequencies and performed with a pair of oscillators between 25kHz and 35k…

Alas, they don't— you can easily demonstrate this for yourself. Startup an audio editor and generate tones at 25k and 28k (make sure you can't hear them— otherwise you have severe distortion screwing up your test) then play both at once. You will not hear a 3kHz tone.

The tone you get from an acoustic beat is not a real tone— it's a perceptual quark that requires you to be able to hear the tones in the first place.

Re: There is no point to distributing music in 24-bit/192kHz format.

#236

Post by nullc »

jaekwon wrote: post #209

The article AFAIK states little about distortions introduced in remixes & samples. I would expect certain high frequency samples, when mixed together to overlap in time, would introduce moire artifacts (beats).

Not unless you pass them through a non-linear filter like a distortion effect.

(yes, the ear-brain system is non-linear too— but apparently it filters out the ultrasonics before they do anything measurable in this regard)

Re: There is no point to distributing music in 24-bit/192kHz format.

#237

Post by Derbasti »

Anechoic wrote: post #59
Derbasti wrote: post #7

He raises a lot of valid points. However... 192 kHz is clearly overkill for listening. Not so for further editing of the data. Same goes for 16/24 bit, however, the difference between 16 and 24 bit is actually audible. 44100 is not a bad sampling rate, but it necessitates very sharp aliasing filters, which are audibly bad. A bit more headroom is well needed there. That bit about intermodulation distortion is complete…

44100 is not a bad sampling rate, but it necessitates very sharp aliasing filters, When you're talking about recording , sure, but in terms of storage and playback, we solved that problem 20 years ago with oversampling.

You will still need a aliasing filter that cuts off between, say, 18 and 22.5 kHz to avoid aliasing noise. That is one sharp filter no matter how you look at it. You can use a high quality, long, linear-phase FIR filter, but you can't cheat physics: sharp filters necesserily introduce distortion, and such a sharp filter so close to the hearing threshold does not go unnoticed.

Re: There is no point to distributing music in 24-bit/192kHz format.

#238

Post by nullc »

blahblahblah wrote: post #190

I mostly agree with the article in the context of distribution of a final mix. However, the article ignores one glaringly obvious reason to distribute in 24/192 format: to allow the listener to be a participant in the creative process, enabling better results for amateur musician listeners who want to sample or remix the audio or for DJs to get better results when altering the tempo for beat matching one track with a…

Yea, and and if the bandwidth/storage is at all an issue 6x size bloat from 24/192 pays for 6 separated tracks. (Actually more, because multitrack is more losslessly compressible while 24/192 is less). If you're already providing multitrack then 24 bit audio would make sense... otherwise, meh.

Re: There is no point to distributing music in 24-bit/192kHz format.

#239

Post by rdtsc »

JangoSteve wrote: post #179

Even without debating the science and signal processing arguments raised... In any test where a listener can tell two choices apart via any means apart from listening, the results will usually be what the listener expected in advance; this is called confirmation bias and it's similar to the placebo effect. It means people 'hear' differences because of subconscious cues and preferences that have nothing to do with the…

There is a perversion going on both ends here. And by perversion I mean a distortion of truth in a bid to make a profit. This is not the worst that can happen, but is just worth mentioning. You probably put more mildly, but I am bit more harsh. Some people are irrational and spend money of stuff that they don't need and another group of people are perpetuating the lies and the marketing in an effort to extract the maximum amount of money from the other group (In other words your basic market setup).

Audiophiles are quite a fascinating group. These are people that can be rather rational in some respects (they could be doing research in some lab somewhere) but when it comes to audio equipment they will shell $2000 for HDMI cables. The salesmen and manufacturers that make these things ("high end" HDMI cables, 192kHz recordings) know this very well and they aggregate around this target set of clients.

I think that is exactly what is happening here. At some point storage capacity is just good enough and one can distribute 48kHz, 16bit audio to everyone. But what do you do next? Everyone is getting that and it is not new and cool anymore. What to do? Well increase the frequency and sell everyone a newer, better, higher fidelity thing, even though objectively human years cannot really hear the difference. Subjectively though, there is a huge difference. If you ask someone who just spent $50 for a 192kHz record if they like it better than say a $20 48kHz one, I bet you 100% of people will confirm that 192kHz sounds better and will be ready to go and buy more.

Re: There is no point to distributing music in 24-bit/192kHz format.

#240

Post by goblin89 »

sjwright wrote: post #78

I must say I get rather irritated when people spend time worrying about dubious 'tweaker' methods to improve their audio, when the most under-performing component of most people's sound equipment also has the lowest-hanging fruit: The room itself. When people ask me where they should spend money to improve the quality of their hi-fi or home theater system, in nearly every case my response will be something like "get…

> Stop being so paranoid about what you think you can't hear, and enjoy the damn music.

Yes. Do a couple of blind tests with your acoustic system first.

> It's true enough that a properly encoded Ogg file (or MP3, or AAC file) will be indistinguishable from the original at a moderate bitrate.

Disagree. This claim seems to be ungrounded compared with others.

I can believe limitations with bit depth and sampling rate (although I'll take a chance to test myself if I get near good enough acoustic system). However, I definitely could discern in a blind test whether music I listened to was stored using lossy format with reasonable bitrate. It's usually quite audible with rock music that involves cymbals.

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