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24/192 music downloads are silly

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421–430 of 443 posts

Re: 24/192 music downloads are silly

#421
There are a couple of things that I would like to point out about digital sampling.

Early on in digital audio, anti-aliasing filters were awful. The ADCs weren't very good either, but the AA filters were bad. Using a higher sampling frequency was one method to help this problem by providing more padding in the frequency domain so that a more gradual AA filter could be used.

Later, this was completely OBE with the advent of oversampling. Most ADCs in use now are oversampling delta-sigma converters operating a very high sampling rates that perform decimation on the output to provide a 16 or 24 bit waveform at the normal 44.1kHz or 48kHz sampling rate. Delta-sigma converters, and high sampling frequencies are actually the basis for Sony's direct stream digital (AKA Super Audio CD).

Today, you can be reasonably assured that an ADC will provide a very clean, low noise, noise output in the vast majority of cases. For music playback, this never mattered anyway. Whether or not the transport of digital audio is at 44.1 kHz or 1 MHz, the quality to the human ear will be the same as long as it was sampled correctly and accurately.

That said - sampling at 44.1 kHz, 48 kHz, or even oversampling, may not capture all that sound has to offer our ears. One thing that can happen with music for instance is beating. Beating occurs when two notes are sounded at slightly different frequencies (say 20,000 Hz and 20,100 Hz) there will be an audible beat at their difference. Where this can come into play is in close mic recordings. If I record guitar A) with an overtone at 30,000 Hz and guitar B) with an overtone at 30,100 Hz, these two would have an audible 100 Hz beat. However, if we filtered and sampled at 48,000 Hz or over-sampled then filtered, we would lose both overtones and the ability to hear that beating.

How important is that beating? Good question - but with live music it's not a problem and with close mic recordings it is. For recording, there are reasons to use higher sampling rates for at least the mixdown process. I still think it's silly to have 192 kHz audio for listening to recordings at home.

Bit depth on the other hand is something I think we could use more of - especially with classical recordings. Audio quantized to 16 bits only provides about 96 dB of SNR. I would much prefer having 20 or 24 bit audio to fully encompass the actual range of human hearing that is closer to 120 dB.

The other thing that cannot go without mentioning, MP3s, AAC, and other lossy audio formats are pretty good - but they DO NOT compare to lossless audio. Having Google, Apple, and Amazon all step up to 44.1 kHz 16-bit audio sourced from equal or greater source material would be huge improvement over MP3s and AAC.

Re: 24/192 music downloads are silly

#422

Earlier quoted context omitted.

Yes. I completely agree. From my perspective, even if one person in a hundred can hear a difference, then I'm going to pay attention. I don't want to boil everything down to meet the average. I think it's fine to release 16/44. I think well produced music sounds excellent in that format. It's one of the reasons the CD has done so well. It's just hifi enough to capture everything. And it's amazing to think this techno…

What's the argument in favor of using extremely high sampling rates though? Using 48 kHz instead of 44.1 seems reasonable (as in the Philips digital compact cassette that never really caught on), giving a little bit of headroom for wider frequency response, moving the filters a little higher or whatever, but I've seen D/A convertors that use 384 kHz , and I just can't fathom what the point is... It smacks of the "if…

I'm not sure there is a compelling reason to distribute final music pieces in 192kHz.

I can only speak from my own experiences, and I record and mix in 24/96 but for reasons that don't really relate to music distribution. When doing further processing, some plugins sound better with their algorithms taking 96k instead of 44k. Every plugin has been written with compromises. And I find I can push hires audio further in the digital domain before unpleasant artefacts arise.

It's very much like image processing. If you take a picture with a cheap basic 1 mega pixel camera and then play with the curves and sharpness, at a certain point smooth graduated colour becomes "posterised". If you take the shot with a DSLR (with 12 bits of each primary colour) then you can push the image a lot further before the posterisation occurs.

I have found the same occurs for audio. I can manipulate the sound with less artefacts when its hires. The plugins sound more transparent and smoother. I tend not to go above 96kHz because this effect is achieved at 96, and 192 (to my ears) sounds no better and I'd just have bigger files and more CPU load from the plugins processing the extra data.

The bandwidth of 96kHz is just short of 50kHz, so if as an added benefit I satisfy the one in a million Geoff Emerick's, then all the better.

But then once the final mix is rendered and no more processing needs to be done, ie for distribution, then this hires advantage seems moot. Maybe there is still some advantage for people or devices that may post process the sound digitally in some way, like a digital equaliser in your playback device, or something like that. But then again, that device could always upsample before processing.

I tend to use 88kHz if the final destination is intended to be CD, and 96kHz otherwise (so there is less aliasing when sample rate converting to 44kHz).

The reason I harp on about the bit depth is because in my experience that is where we are falling short. If I take my hires sources and convert to 44 or 48 with a high quality SRC I hear no difference at all. But when I change to 16 bit the difference is enormous. There is always a degredation. And it's never a good thing. It seems silly to just be throwing away that bit depth because of a 1982 format that people aren't even listening on anymore.

Also on the topic of SRCs, this site has some interesting comparison. For the record I do my SRC conversion with iZotope RX 64 bit SRC. http://src.infinitewave.ca/

So in conclusion, I want 24 bit tracks. If they're given to me as 44, 96, 192... whatever. As long as they're 24 bit. Enough with the 16 bit! :D

Re: 24/192 music downloads are silly

#423

There's a special irony to the fact that this high fidelity audio format is being promoted by Neil Young. Young's a rock musician. He's been around loud noises (e.g. rock concerts) most of his life. He's also 69 years old. Our ability to hear high frequencies decreases dramatically with age and exposure [1]. If anyone were able to discriminate 24/192 from 16/44.1, it sure as heck wouldn't be an elderly rock musician.…

To be fair, I have worked with older sound engineers, and they can hear a lot of audio artifacts that I miss, just because they've been paying closer attention for a lot longer than I have, much in the same way my wife (who plays violin 6+ hours most days) can hear tuning and pitch problems better than I can. High frequency limiting is not the only artifact that results from data compression.

Yeah. I worked for a long time as a professional musician in an orchestra. I fucked up my hands from practising too much, so I switched career.

I can reliably hear a pitch difference of ~0.2hz at this site: http://tonometric.com/adaptivepitch/

and that is after 15 years in a symphony orchestra having my ears blasted by the brass and percussion section (with a demonstrated hearing impairment from my time in the orchestra).

Re: 24/192 music downloads are silly

#424
post #412

Earlier quoted context omitted.

> but not all these people are idiots Not to be picky, but it bugs me to see when people talk about two different things and don't understand each other. Intelligence is not a linear value that could be compared like "person1 intelligence > person2 intelligence". With both of these terms there are always skipped implication of the area of intelligence. By "idiots" he meant "small amount of/incorrect knowledge in the…

If you're going to be "picky", please be picky about something you understand. A "small amount of/incorrect knowledge" is ignorance , not a lack of intelligence. When you label someone an idiot you're not talking about his lack of knowledge. You're talking about his intelligence. Now, if by "idiots" he means "ignorant people" then he's using the word incorrectly. But there's no actual indication that's what he meant.…

What you are referring as "basic intelligence" is actually a combination of neuroplasticity and general knowledge. Neuroplasticity is a speed at which brain can learn new things, but even then you can't say "person1 neuroplasticity > person2 neuroplasticity". That is because brain is composed of many parts that can have different plasticity. Also neuroplasticity (i.e. "intelligence") is not static and can even change over time depending on what parts of the brain are most active.

Re: 24/192 music downloads are silly

#425

I once spent ~2 hours explaining all of this (well maybe not all of it) to a friend of mine who was studying sound design at the time. He didn't believe me. I even transcoded some 24/192 FLAC Pink Floyd I had lying around and made him do a double blind test to show him that he'd prefer the slightly louder song every time, even if the louder song was 192kbps vs the FLAC. He did. He still doesn't believe me. He still t…

> Some people buy $500 wooden knobs to make their volume pots sound better. (or was that a hoax? i can't tell anymore) Some people buy small pyramids to elevate their cables off the floor, some people buy mats to put onto your CDs before putting the CD in a player ( http://dagogo.com/millenniums-m-cd-mat-carbon-cd-damper-revi... ), some people buy $1000+/meter digital interconnect cables ( http://www.theabsolutesound…

Had anyone metioned DVD Rewinder? http://www.dvdrewinder.com/index.html Also demagnetizer is a cool device http://www.acoustic-revive.com/english/rd3/rd3_01.html

Re: 24/192 music downloads are silly

#426

Earlier quoted context omitted.

>I just think folks should be left to their own devices to enjoy an avocation as they please. Only if they shut up and never tell other people that should be listening at 24/192. However, the people being complained about here spout nonsense like that all of the time.

Wait! Who's telling who what? I think you find you have it backwards. I don't hear anyone here telling you that you should be listening at 24/192. Go look at all the comments and count them up. All I hear is people saying that you should be listening at 16/44, because it sounds exactly the same, or even sounds better, and if you think otherwise you're obviously an idiot, stupid, audiophool who spends $5000 on a power…

The guy that wrote this article didn't write it because snobs were being reasonable...

Re: 24/192 music downloads are silly

#427
post #412

Earlier quoted context omitted.

If you're going to be "picky", please be picky about something you understand. A "small amount of/incorrect knowledge" is ignorance , not a lack of intelligence. When you label someone an idiot you're not talking about his lack of knowledge. You're talking about his intelligence. Now, if by "idiots" he means "ignorant people" then he's using the word incorrectly. But there's no actual indication that's what he meant.…

What you are referring as "basic intelligence" is actually a combination of neuroplasticity and general knowledge. Neuroplasticity is a speed at which brain can learn new things, but even then you can't say "person1 neuroplasticity > person2 neuroplasticity". That is because brain is composed of many parts that can have different plasticity. Also neuroplasticity (i.e. "intelligence") is not static and can even change…

Yet again, none of what you've written here is actually true. I suggest you peruse the wiki page.

Re: 24/192 music downloads are silly

#428
post #131

Earlier quoted context omitted.

> some people buy mats to put onto your CDs before putting the CD in a player An 80-minute, 700 MB CD-R fits 80 * 60 * 44100 * 2 * 2 / 2^20 ~= 807 MB of audio. Why is that? The 100MB difference is not just due to the audio TOC being of smaller size than the ISO9660 or UDF file system metadata. It's also because of differences in error correction. I don't have the spec on hand but I recall from when I was investigatin…

Uh, no. Bit-perfect ripping is trivial and routine, and tools like the AccurateRip DB (which has checksums for around three million different titles you can use to verify the checksums on your own rips) and the CUEtools database (which has recovery records you can use to correct bit errors on your own rips) prove it. I routinely get bit-accurate single-pass high-speed rips--no "paranoid" settings or re-reads--of disc…

> bit-accurate single-pass high-speed rips

"military-grade encryption"

Re: 24/192 music downloads are silly

#429

Earlier quoted context omitted.

Right, 22,050hz looks exactly like a triangle wave on a computer screen. The thing is that a triangle wave is composed of a fundamental sine wave (22kHz), and a series of ascending odd harmonics above it. So after the filters nix everything above 22kHz it looks exactly like a sine wave on a scope. So you're right that you lose information as you go higher in frequency, but there is also commensurately less need for i…

Sure 22,050hz and 11,025hz get smoothed out into perfect sine waves and the human ear can't hear 22Khz anyway. But the Nyquest frequency isn't some magical threshold that you cross and suddenly everything is perfectly preserved. It's a folding frequency that determines where aliasing is going to occur, or rather where it's not going to occur. A 44Khz sampling rate is based roughly on western tuning (440Hz A) and make…

Yes, and also remeber that as you approach the nyquest frequency, the ability to encode phase is lost. People always talk abou sampling capturing different frequencies but they forget to think about phase.

Re: 24/192 music downloads are silly

#430
post #90
post #44

Earlier quoted context omitted.

Let's do the math. If I didn't screw it up (and I probably did), an 8k iphone 6 would be around 1600 dpi.

Imagine being able to use a physical magnifier to see more information on the screen. Wouldn't that be great? at least for a curious child?

I kind of had that effect at a trade show a while ago where they had huge demo displays like 12 foot /6000 pixels across and I couldn't see all the detail at a usual viewing distance but could make it out in small areas by wandering up close. It was kinda cool. I'm not sure it would have that much value in a domestic setting but in something like a museum / gallery could be good.
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