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24/192 music downloads are silly

xiph.org

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Re: 24/192 music downloads are silly

#231

Earlier quoted context omitted.

Pretend your headphones only moved with 8-bit resolution. There is no possible way the experiment could derive a useful conclusion, but you might trick yourself into thinking it did. Especially if your sample size was 10,000 people. More realistically, the participant might choose music for which no 24-bit recording exists. It's very important to control for every variable. It's actually not possible to gather info a…

More realistically, the participant might choose music for which no 24-bit recording exists. Well, obviously we'd need to have a limited set of music selections for which we have 24-bit recordings. As you suggest, I expect the biggest impact on playback fidelity is going to be other factors like the noise in the system (likely a PC) and such. But the flip side of it is that's also a good real world test. If the only…

But the flip side of it is that's also a good real world test. If the only time you can tell a difference is to be in an acoustically dead room with top end equipment, then the higher sample rate really isn't worth it

Hey, that's a great point! Hadn't considered that.

Proving "most people can't tell the difference between 24-bit and 16-bit in real-world settings" is less compelling than proving "no one can ever tell the difference," but it's still very relevant.

Re: 24/192 music downloads are silly

#232

Earlier quoted context omitted.

> 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…

When someone spends money on something in a silly way, do you consider them to be an idiot? Would you make the same statement about someone who spends 200$ on a bottle of scotch versus buying a 35$ bottle? Let the 'idiots' spend their money driving an industry that is combining the creation of electronics with functional art. I'm not sad to see a $40,000 DAC. I don't have to buy it, and it's cool to know someone buil…

If you enjoy music (who doesnt) and are bending toward learning electronics I highly recommend projects like Twisted Pear kits and build yourself a DAC. http://www.twistedpearaudio.com/landing.aspx

The other fun stuff is building your own Speaker kits, hook all this up with a Pi Music Box and you have yourself a kind of home made Sonos. http://www.woutervanwijk.nl/pimusicbox/

Re: 24/192 music downloads are silly

#233

The author confuses sampling theory with reality. Sampling theory says you can reconstruct a signal by sampling it at least twice per cycle. So 44.1KHz is an adequate sampling rate for an 22.05Khz signal. Unfortunately to make Digital-to-Analog conversion work according to theory, you must first construct an ideal analog filter which filters out everything above 22.05Khz while leaving everything less than 22.05Khz un…

Both of the points you bring up are unrelated to the format in which files are stored. Sure, they would be requirements for the format that gets sent to a primitive DAC. But the answer to your problem is basically contained in your post: before the signal is sent to your theoretical DAC component, the signal's rate could be digitally upsampled by a factor of 2 (to avoid artifacts), and dither could be applied to eliminate any jitter problems (with the unnoticeable side-effect of raising the noise floor to -66dB, in the case of 16 bit depth).

Anyways, as dfox mentionned, most sound cards nowadays use sigma-delta DACs, which do not need upsampling as they do not involve a filter in the way you described.

Re: 24/192 music downloads are silly

#234

Earlier quoted context omitted.

> 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…

When someone spends money on something in a silly way, do you consider them to be an idiot? Would you make the same statement about someone who spends 200$ on a bottle of scotch versus buying a 35$ bottle? Let the 'idiots' spend their money driving an industry that is combining the creation of electronics with functional art. I'm not sad to see a $40,000 DAC. I don't have to buy it, and it's cool to know someone buil…

You are mixing two things. There is a difference between Intel charging you >$1K for a CPU that is 5% faster (in games) than overclocked $300 one versus scammer selling magical power cables (made by gypsy virgins in Romanian monastery on top of the highest mountain, in full moon) to some rich retards.

$40,000 DAC? someone really went ahead and fabbed their own silicon (~$1mil for low volume run)? or did they maybe picked up $100 (at most) part, put it in a shiny box and started looking for suckers?

Do you even realize what $40K gets you? we are talking military grade Agile^^key'hole/RohdeShwartz multi gigahertz arbitrary waveform generators here, not some pityfull audio stuff.

Here are some examples of multi thousand dollar scams: http://www.lampizator.eu/LAMPIZATOR/REFERENCES/wadia%20WT%20... http://www.lampizator.eu/LAMPIZATOR/REFERENCES/Goldmund/gold... http://www.lampizator.eu/LAMPIZATOR/REFERENCES/THETA%20Unive...

Audiophoolery is on the same level as creationism, it only works on uneducated simple minds with no metacognition.

Re: 24/192 music downloads are silly

#235

I remember when CDs first came out and Neil Young was very critical of their sound, and I believe he was entirely justified in his criticism. When they first came out CDs were Record Company's poor stepchildren, and they were treated very poorly. I believe the engineers mastering CDs were given tapes that were several generations away from the original master tapes, and I suspect they may have even been already equal…

I suspect something else was happening too: Recording techniques were adapted to the problem of making something sound good after recording, mastering, cutting, and playback. This probably meant getting away with some shortcuts that would be masked by subsequent processing. The perfection of the digital medium unmasked those things.

Re: 24/192 music downloads are silly

#236

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.

[deleted]

Re: 24/192 music downloads are silly

#237

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…

Preface: I consider myself an audiophile, but keep reading before you judge. I completely, wholeheartedly agree with the original article and the science behind it. There's no question that our hearing just isn't good enough to discern the minute differences between sound of sufficient quality (which is well defined in the Xiph article). However, all I'll say is, it's very different to hear or feel a difference, than…

>However, all I'll say is, it's very different to hear or feel a difference, than to prove it 100% without any doubt in the exacting conditions of an ABX test. You behave differently and aim your listening at different things in the special case of critical testing, than when normally listening.

so what you are saying is you know what sounds better if you read the label BEFORE listening to it? :) There is almost always a difference, no one is claiming otherwise. Pointing which one is closer to the original (not "better", because "better" might mean louder/overdriven bass) is the real test, and EVERY SINGLE audiophool to date fails at this point - Randi foundation did run a $1M pot for someone to spot a difference between 'audiophile grade' power/speaker cables versus coat hangar at one point.

http://www.bostonaudiosociety.org/bas_speaker/wishful_thinki...

Re: 24/192 music downloads are silly

#238
post #47

Earlier quoted context omitted.

I wouldn't say being a data compression geek makes anyone a master of DSP or of psychoacoustics. The basic issue with 16-bit is that low level details like reverb tails and hall ambiences or very quiet musical passages get the equivalent of 14-bit (f) 12-bit (mf) to 8-bit (ppp) sampling. This sounds noticeably grainy and digital. It's not about total dynamic range or sine waves, it's about the fact that human ears ca…

I'm not sure what you mean about quieter sounds having less resolution. The point of having a 16-bit representation of a sample is that you pick the single point on the 65,536-point (logarithmic) line that is closest to the sound pressure level at that time. It's not like the points "below" your sound add up or anything. A loud sound gets a high number, and a quiet sound gets a low number. Both cases have the same pr…

PCM audio sampling is linear, not logarithmic.

There are log sampling systems - e.g. A-law and u-law are used in telephone codecs.

But uncompressed audio formats like PCM WAV are 100% linear. (Or should be, near enough.)

Re: 24/192 music downloads are silly

#239

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…

The article is correct, but it's not true that nobody can't tell the difference between an MP3 and a FLAC.

I've personally done blind A/B testing in my (then) studio to discover the point at which I can't distinguish between MP3 and uncompressed audio. These days the encoders are really good, so it gets real hard at around 256kbps. I'm confident I could reliably pick out 192kbps though.

Re: 24/192 music downloads are silly

#240

Earlier quoted context omitted.

>If you are going to reduce them to the basest level of what the purpose for a speaker or headphone is, to reproduce the input sound, then yes, they are shitty, because they are not good at that. Though I don't personally like the cold, base heavy sound of Beats, I don't really get how you could know this, because most people have no idea what a piece of music should sound like. They know how they think it should sou…

So, uh, we can measure the frequency response made by headphones. http://www.innerfidelity.com/content/headphone-measurement-p... http://www.headphone.com/pages/evaluating-headphones This is a pretty scientific matter - when I say "the purpose is to reproduce the input sound", we can tell exactly what is supposed to be reproduced, and we can tell exactly how capable the speaker is of reproducing it. Some exceptions h…

> This is a pretty scientific matter - when I say "the purpose is to reproduce the input sound", we can tell exactly what is supposed to be reproduced, and we can tell exactly how capable the speaker is of reproducing it.

You are assuming the song was mixed by someone wearing headphones that perfectly reproduce the input sound. Suppose the person who mixed a song was using beats headphones or other headphones that audiophiles consider inferior but that they know the majority of people use to listen to music. Wouldn't that then mean Beats headphones actually provide the listener with the actual, intended experience?

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