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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)

#151

Post by black_knight »

rahimnathwani wrote: post #35

The article says "I've run across a few articles and blog posts that declare the virtues of 24 bit or 96/192kHz by comparing a CD to an audio DVD (or SACD) of the 'same' recording. This comparison is invalid; the masters are usually different." It may be simultaneously true that: A) Humans cannot tell the difference between 44.1kHz/16-bit audio and any higher resolution, and B) For a particular song, the best commerc…

I usually A/B test the different versions before choosing my canonical one. I will listen to the same sections in each version, flipping back and forth to hear the differences. It is incredible how much finding the right master improves the experience of listening to a track. Often times that means I end up with a hi-res version, but not always.

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

#152

Post by PaulDavisThe1st »

speak_on wrote: post #149
PaulDavisThe1st wrote: post #133

Earlier quoted context omitted.

But the energies of the signal present above the Nyquist frequency (22050Hz in this case) are almost always incredibly weak, and double blind testing rarely shows any indication that humans can actually hear the aliasing.

Mixing process often involves hundreds of tracks, and if each introduces aliasing, this can become a problem. Some engineers do swear by "the final mix is 16/44.1 so why mix at a different resolution?" mantra - that's fine too.

This is false. Aliasing is not additive in any meaningful way.

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

#153

Post by PaulDavisThe1st »

nok22kon wrote: post #148
PaulDavisThe1st wrote: post #129

Earlier quoted context omitted.

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.

I remember using Adobe Audition for resampling audio, this site shows I had good intuition your software is among the best, but not pitch black best :)

Yeah, we use Secret Rabbit Code for ours, though we have access to the sox code now and that is "perfect". We might change to that as the default sometime this year.

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

#154

Post by pimeys »

az226 wrote: post #147
pimeys wrote: 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…

What’s the quality of this trove? As in bitrate or similar.

Depends. I'm more into finding certain masters. And some of the albums are DSD tape transfers. DSD if that was the original recording format, if it was mixed and PCM was needed, DXD flac.

And so many CDs of course.

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

#155

Post by speak_on »

PaulDavisThe1st wrote: post #135
speak_on wrote: post #95

Earlier quoted context omitted.

44.1 is "enough" only in theory. This assumes a physically impossible steep filter. Realistically, frequencies around 20 kHz will create audible artifacts (aliasing). So yes, a trained ear can tell the diffrenece between 44.1 and even 48 kHz. Like many other commenters in this thread, you are mixing up math theory with physical limitations of AD/DA converters. Oversampling is a common way to address this limitation,…

> Realistically, frequencies around 20 kHz will create audible artifacts (aliasing) The energy of the signal components above the Nyquist is generally very low, and very few double blind tests have given any indication that humans can detect the resulting aliasing (even though many people claim to be able to do, almost always in non-double-blind environments). Badly written digital synthesis can generate high energy…

Genereally very low for a single track? What about 200 tracks? Badly written synthesis, or badly recorded live instruments, or bounced and re-bounced dozens of times... we are not talking about the quality-defining aspect here. You can produce an excellent mix on KRKs connected directly to a MacBook.

This space is not driven by a single precise formula. 48/96 kHz helps some engineers to produce better sounding mixes. Can everyone hear the extended range of Adam tweeters? Probably not. But some can, and they benefit from that. Even if there is no double-blind study to prove this in absolute terms.

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

#156

Post by nullc »

Cider9986 wrote: post #81
stego-tech wrote: post #54

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…

I can't hear the difference between 128 kbps opus and FLAC.

> I can't hear the difference between 128 kbps opus and FLAC.

A reasonable definition of transparency for high bitrate compressed audio is "Can the worst files be distinguished by a listener trained in what artifacts sound like". Maybe also add in having to use a high discrimination listening setup, including not running excessively loud (increases masking).

If that's not the test you're doing, it's unsurprising. At moderately high bitrates no one can reliably distinguish them on arbitrary samples: most inputs are easy.

If you test on known-difficult "killer samples" you'll probably easily distinguish them, even without first being shown what to look for, and certainly after.

During the development of Opus I created many 'trained listeners' and selected many killer samples, and I don't recall* ever encountering a tin ear that couldn't be taught to ABX any high rate samples, though some people are obviously much better at it.

I'm not sure I'd recommend it though: learning to identify artifacts has a frequent side effect of making low rate audio like the HE-aac used in SirusXM absolutely intolerable. I'm bothered by it even when I hear cars driving by using it. :)

[*] My memory for such things sucks, so I could be wrong-- but my point that it's not expected remains.

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

#157

Post by vor_ »

speak_on wrote: post #121
vor_ wrote: post #110

Earlier quoted context omitted.

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: overs…

Oh, dear, that AES 2014 paper from Meridian (which was trying to push its controversial proprietary MQA audiophile system the same year) was widely criticized on audio forums when it came out, ranging from the rectangular dithering method to the use of a hard metal tweeter that could cause IM.

Do you have more convincing sources?

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

#158

Post by geraldmcboing »

PaulDavisThe1st wrote: post #117
geraldmcboing wrote: post #109

The OP is a bit off with their description of why pro audio engineers work in higher bit rates and sample rates. We use 24bit to preserve low level sounds eg reverb, breaths etc and use 32bit float when recording as the headroom is so massive clipping is not an issue (other than of course still neeing to avoid overloading microphones with max SPL - cleanly recorded distorted sound is still a fail). Unclipping 32bit f…

Have you ever actually checked the number of actual bits your ADC can use? Most 24 bit converters struggle to get to 18 bits. Nobody uses 32 bit float for recording (to do so is just to capture at least 10 bits of noise, most of that being brownian); its strictly a format for mixing and processing. You don't get any more resolution from 32 bit floating point than you do from 24 bit integer formats, but the result of…

Dude I've been doing sound design on films using these techniques for years. There is zero 'woo' involved, it is ALL practical evidence based use. I've been using 32bit float multitrack field recorder by Sound Devices MixPre10-II professionally for many years now. The recorder has three preamps per mic input, each gain staged to provide optimum signal to the 32bit float AD. Read this to clarify your thinking: https://www.sounddevices.com/32-bit-float-files-explained/

Surely you understand a recording made at 48kHz has a max freq response of 24kHz and played at half speed that max freq is 12kHz and at quarter speed only 6kHz. You can very clearly hear the filter cut off due to Nyquist. Record at 192kHz with mics capable of 100kHz capture and when played at quarter speed, the sound is full spectrum because there is no truncated frequency response. And when I load a 192kHz recording to izotope RX I can literallu see the harmonics going up to 96kHz. (not with every sound of course)

I repeat, i am not talking about 'normal' listening. I am talking about an industruy you have no knowledge or lived experience with, so spare me the incorrect claims about what can & cant be heard.

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

#159

Post by nok22kon »

PaulDavisThe1st wrote: post #150
nullc wrote: post #146

Earlier quoted context omitted.

> Nobody uses 32 bit float for recording Yes they do, almost all high end field recorders used for film work are 32-bits now and have been for much of the last decade, often with some fancy preamp integration so that there is no expertise required for gain staging the recording. (I believe the implementations use a second matched 24bit ADC with 48 dB less gain in front of it). The result obviously doesn't have a nois…

There are precisely zero 32 bit ADCs in existence. There are ADCs that will provide 32 bits per sample but that's entirely different. Current technology limits the bit depth to 18-22 bits and going beyond that you'd be very quickly recording brownian (atomic) noise anyway. The point about 32 bit float is that it is a useful format for mixing, editing and general processing, so it is widely used in digital audio tools…

Rode NT1-A 5th gen microphone claims 32-bit float output, insisting it will not clip peaks

so maybe they do sample at 24 bit at a well chosen gain level and then convert to 32 bit float, with the max 24 bit value being above 1.0 float

or as GP said, use two separate ADCs at two different gains and combine their output

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

#160

Post by geraldmcboing »

PaulDavisThe1st wrote: post #150
nullc wrote: post #146

Earlier quoted context omitted.

> Nobody uses 32 bit float for recording Yes they do, almost all high end field recorders used for film work are 32-bits now and have been for much of the last decade, often with some fancy preamp integration so that there is no expertise required for gain staging the recording. (I believe the implementations use a second matched 24bit ADC with 48 dB less gain in front of it). The result obviously doesn't have a nois…

There are precisely zero 32 bit ADCs in existence. There are ADCs that will provide 32 bits per sample but that's entirely different. Current technology limits the bit depth to 18-22 bits and going beyond that you'd be very quickly recording brownian (atomic) noise anyway. The point about 32 bit float is that it is a useful format for mixing, editing and general processing, so it is widely used in digital audio tools…

Why are you obsessed with DAC? Its the ADC that is WHY we capture 32/192.
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