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A Phoenix record store owner set the audiophile world on fire

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Re: A Phoenix record store owner set the audiophile world on fire

#301

Post by ncmncm »

naikrovek wrote: post #253
Night_Thastus wrote: post #248

"In the world of audiophiles — where provenance is everything and the quest is to get as close to the sound of an album’s original recording as possible — digital is considered almost unholy." Out of context of the rest of the article, this is total nonsense. While some in the audiophile scene like going analog, none of them debate against the truth that objectively , vinyl is far lower quality. Vinyl doesn't have ne…

if your DAC is a DAC, truly (that is not a high bar) then the audio that comes out of it is a perfect reproduction of the audio that went into the ADC that produced the digital audio, provided it is a true ADC (also not a high bar at all). Nyquist theory proves it. The Ogg people have a fantastic video explaining this. Technology Connections on YouTube has a video about it as well (the Ogg video explains things bette…

I used to believe this, based on the mathematical proof referred to. But every proof relies on assumptions, treated as axioms, ideally (but rarely) all noted.

This particular proof assumes that the clock is perfect, with no jitter or delay between one place it is used and another. There are more ways for a clock and uses of it to vary than you probably imagine possible.

It also assumes the A/D and D/A converters produce exactly correct results, which none do. We expect them to be close enough.

So in fact the output is as close to the same as the input as anybody cared to ensure, subject to cost, component tolerances, and amount of attention spared.

In practice, it is almost always as close to exact as anybody listening cares about (and better than a phono needle could manage). But there are ways for digital systems to produce bad results, by happenstance, laxness, or just normal aging.

Few ever check the calibration of their equipment.

Re: A Phoenix record store owner set the audiophile world on fire

#302

Post by smat »

adrian_b wrote: post #285
yobbo wrote: post #271

Earlier quoted context omitted.

Audiophiles sometimes claim they can hear artefacts of the "low" sample rate 44.1 kHz, and only 16 bit samples. Nowadays there exists audio files recorded in up to 96 kHz with 24 bit samples.

The sample rate 44.1 kHz is objectively "low" in the sense that if you have to want a passband of 20 kHz, then extremely sharp low-pass filters must be inserted before the ADC. So sharp low-pass filters are extremely difficult to implement as analog filters with reproducible characteristics. Even when they are implemented as digital filters, as in most modern equipment, i.e. the audio ADC uses a much higher sampling…

While the ideal filters have an infinite long inpulse response and are therefore „non realizable“, shorter filters simply increase the noise level. With filters of 100ms length you are already at SNRs that is far from what any human can handle (think of hearing rustling leaves while standing next to a jet engine).

You will however need to accept delay from the lowpass filter, which is fine for music reproduction.

So while these effects are measurable with very expensive equipment, they are in all metrics orders of magnitude better than any analog equipment.

Re: A Phoenix record store owner set the audiophile world on fire

#303

Post by mellosouls »

Night_Thastus wrote: post #248

"In the world of audiophiles — where provenance is everything and the quest is to get as close to the sound of an album’s original recording as possible — digital is considered almost unholy." Out of context of the rest of the article, this is total nonsense. While some in the audiophile scene like going analog, none of them debate against the truth that objectively , vinyl is far lower quality. Vinyl doesn't have ne…

Reminds me of the famous John Peel quote:

"Somebody was trying to tell me that CDs are better than vinyl because they don't have any surface noise. I said, 'Listen, mate, life has surface noise”

Re: A Phoenix record store owner set the audiophile world on fire

#304

Post by dr_kiszonka »

quickthrower2 wrote: post #293
SideburnsOfDoom wrote: post #287

Earlier quoted context omitted.

There's always a threshold though. Proof by contradiction: if there's no threshold, then sound fidelity can in theory be infinitely precise. But nature does not work that way - at Planck length distance breaks down, at the width of a carbon atom the resolution of a vinyl surface ends, etc.

Audiophiles talking about quantum fluctuations in their analog recordings :-)

I used to have this exact problem with my cables! For this reason, I've spent the last six months building quantum shielding for audio cables, with genre-specific time crystal coatings. It is now available in my Qtsy store, if anybody is interested!

Re: A Phoenix record store owner set the audiophile world on fire

#305

Post by Shorel »

Night_Thastus wrote: post #248

"In the world of audiophiles — where provenance is everything and the quest is to get as close to the sound of an album’s original recording as possible — digital is considered almost unholy." Out of context of the rest of the article, this is total nonsense. While some in the audiophile scene like going analog, none of them debate against the truth that objectively , vinyl is far lower quality. Vinyl doesn't have ne…

> But with good recordings and mastering

That's the issue here. The loudness war made any CD mastering a race to make the most compressed track, just to sound louder than the competition.

Technically, digital should sound better. The technology is better. Sound engineers are making sure this is not the case.

Re: A Phoenix record store owner set the audiophile world on fire

#306

Post by 112233 »

naikrovek wrote: post #253
Night_Thastus wrote: post #248

"In the world of audiophiles — where provenance is everything and the quest is to get as close to the sound of an album’s original recording as possible — digital is considered almost unholy." Out of context of the rest of the article, this is total nonsense. While some in the audiophile scene like going analog, none of them debate against the truth that objectively , vinyl is far lower quality. Vinyl doesn't have ne…

if your DAC is a DAC, truly (that is not a high bar) then the audio that comes out of it is a perfect reproduction of the audio that went into the ADC that produced the digital audio, provided it is a true ADC (also not a high bar at all). Nyquist theory proves it. The Ogg people have a fantastic video explaining this. Technology Connections on YouTube has a video about it as well (the Ogg video explains things bette…

> Nyquist theory proves it.

Only if your signal is infinitely repeating in time, with no start or end. Otherwise, it's spectrum is not band limited.

Is your ADC input such a signal?

Re: A Phoenix record store owner set the audiophile world on fire

#307

Post by e63f67dd-065b »

timpattinson wrote: post #264
naikrovek wrote: post #253

Earlier quoted context omitted.

if your DAC is a DAC, truly (that is not a high bar) then the audio that comes out of it is a perfect reproduction of the audio that went into the ADC that produced the digital audio, provided it is a true ADC (also not a high bar at all). Nyquist theory proves it. The Ogg people have a fantastic video explaining this. Technology Connections on YouTube has a video about it as well (the Ogg video explains things bette…

The Shannon-Nyquist sampling theorem only defines the sample rate to perfectly reproduce a signal of a certain bandwidth. It says nothing about noise, distortion, dynamic range. In these areas it is impossible to create a "perfect" DAC, although granted the best DACs are indistinguishable from perfect as far as human perception is concerned.

I'm unfamiliar with the mathematics involved, but this is what Wikipedia says the theorem states:

> If a function x(t) contains no frequencies higher than B hertz, it is completely determined by giving its ordinates at a series of points spaced 1/(2B) seconds apart

I took this to mean that it's any continuous function x(t), including amplitude information. I took a quick read through the proof and that's correct as far as I can tell.

Does that not mean that "noise, distortion, and dynamic range", as they are all encoded in the continuous function that is air pressure over time, can be perfectly captured and reproduced? All you need to do is throw out all information outside of human hearing range to have no frequencies higher than B hertz, and that's all you need for perfect reproduction.

If there exists a transformation f(x(t)), then said transformation can also be captured by the same sample, can it not?

Re: A Phoenix record store owner set the audiophile world on fire

#308

Post by kalleboo »

allears wrote: post #45

People who claim CDs have more dynamic range than analog are missing the point. Think of it in terms of graphics. 8 bit graphics can represent totally black, or totally white. That's a complete dynamic range. But it's the in-between shades that require more bits to specify. It's the same with audio. It's not how soft or how loud a recording can get. It's the subtle shades of variation. 16 bits is pretty good, but not…

Speakers can't move at the precision and speed required for stair-stepping to be a real thing.

Re: A Phoenix record store owner set the audiophile world on fire

#309

Post by flaghacker »

e63f67dd-065b wrote: post #307
timpattinson wrote: post #264

Earlier quoted context omitted.

The Shannon-Nyquist sampling theorem only defines the sample rate to perfectly reproduce a signal of a certain bandwidth. It says nothing about noise, distortion, dynamic range. In these areas it is impossible to create a "perfect" DAC, although granted the best DACs are indistinguishable from perfect as far as human perception is concerned.

I'm unfamiliar with the mathematics involved, but this is what Wikipedia says the theorem states: > If a function x(t) contains no frequencies higher than B hertz, it is completely determined by giving its ordinates at a series of points spaced 1/(2B) seconds apart I took this to mean that it's any continuous function x(t), including amplitude information. I took a quick read through the proof and that's correct as f…

Yes, a perfect recording of the amplitude of a function at a frequency of at least 2B contains enough information to perfectly reconstruct that function. Reaching this frequency is not that hard, but getting a perfect amplitude measurement is. This is where "noise, distortion and dynamic range" come in, they act as disturbances to the amplitude.

Re: A Phoenix record store owner set the audiophile world on fire

#310

Post by npteljes »

isatty wrote: post #124
criddell wrote: post #69

Earlier quoted context omitted.

Can you reliably hear a difference between a lossless file and a modern high bit rate MP3 (or other lossy format)? I can't, but then I have tinnitus...

Depends on the music. 320k mp3 is actually pretty good. Anyway in this case I want a studio promising that their records were pressed from a high quality master to actually use a high quality master. It doesn’t matter if I can’t distinguish it. Just because a Camry can also transport my ass from a to b does not mean the Porsche dealership gets to sell me one over another car I specifically wanted.

Yes, this is a very important point that a lot of people miss. How are people supposed to learn to appreciate a genuine thing is if they are constantly swindled?

Also, people are not rational beings first and foremost. Sentimentalism makes them vulnerable, but that shouldn't mean that it's open season for swindlers. I can make my origami from any paper basically, but it feels good in a certain way to order special paper from Japan just for this reason. And I'd feel cheated if the paper turned out to be from anywhere else - despite being no different on a material level.

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