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> Audiophiles might point out that analog audio sources can theoretically hold details you can't hear in digital. This is true because values in analog media ar

> Audiophiles might point out that analog audio sources can theoretically hold details you can't hear in digital. This is true because values in analog media are continuous. Over imperceptibly short periods of time, the numbers that represent different values on a sound wave in a digital recording jump instantaneously from one discrete value to another with no gentle slope between. Analog signals instead form smooth curves, so at some level they can contain tiny variations in slope that are too subtle for the digitization of that signal to represent. > The problem with analog superiority in general is that, when that digital signal is of standard CD quality (44,100 samples per second at 16-bit resolution), whatever details in the analog signal are too subtle to be captured digitally are also too subtle for me or really most people to hear. This so wrong it makes my head hurt. It's 2023 and people still think that digital doesn't produce smooth curves and that typical analog media -- cassette tape no less -- can store more details than a CD. These people need to be tied to a chair, have their eyelids taped open, and force-fed Monty Montgomery's video. https://www.youtube.com/watch?v=cIQ9IXSUzuM https://www.youtube.com/watch?v=cIQ9IXSUzuM

zimpenfish 4y ago
Has anyone ever worked out / quantified what kind of depth difference in a vinyl groove you'd need to beat the CD digital signal for "too subtle to capture"?
- TheOtherHobbes 4y ago
  You need roughly an extra 60dB of dynamic range to match CD. The largest groove deviation on vinyl - nominal 0dB - is around 23um. To add 60dB you have to multiply by 1000, which gets you 23mm. And increase the thickness correspondingly. This has has tragic consequences for the size and weight of the disk. Although it wouldn't be playable because the stylus would be pulling hundreds of Gs. For the short period for which it survived it would be hot enough to melt the vinyl. (Actually it would probably catch fire.) You can imagine an optical reader - the've been built for for vinyl, but for some reason they never caught on - but if you're going to do that you may as well have a sub-micron digital data stream in a much smaller disk.
  - KerrAvon 4y ago
    There’d still be a market for optical vinyl readers — a playback mechanism that didn’t degrade your mint copies of old LPs would be treasured by a lot of people. The old laser turntables never caught on due to the expense — $10,000 a few decades ago, in those dollars at the time — and due to dust and other imperfections causing severe audio glitches that wouldn’t show up or would be less severe with a stylus. These problems should be solvable with current technology, though.
  - sbaiddn 4y ago
    The extra information could be stored in the non-audible spectrum of the vinyl. But the reconstruction would be complicated and it would wear out fast. There were some ultrasonics technologies that were aborted when Phillips introduced the CD
function_seven 4y ago
Ha, I knew where that link was going before I clicked it. That is the go-to video to dispel the "stair step" misconception. It worked wonders for me when I first watched it. While many time-machine inventors would go back and kill Hitler, I wouldn't. I would find the first person to draw a "digital sine wave" and handle that problem.
- TheOtherHobbes 4y ago
  If you really understand digital sampling, there's actually quite a lot wrong in that video. The "16-bit is enough" line is absolutely wrong, because quantisation noise has a very uneven spectrum which is nothing like white noise. It has peaks at certain subdivisions of the sample rate which are quite a way above inaudibility. Which is why dither was invented - to smooth out those peaks. The "44.1kHz is enough" line is also wrong because there's no such thing as a perfect reconstruction filter. (It's mathematically impossible to build a perfect brick wall filter that works in real time.) Real reconstruction filters have trade-offs and the distortions always become more audible and obvious around Nyquist. They're less obvious at higher sample rates. There are also inter-sample peaks which can clip in the reconstruction filter and which are easier to avoid at higher sample rates. Digital also suffers from clock jitter. Early converters were just plain nasty, but these days jitter is barely a problem on cheap converters and not audible at all on pro-grade hardware. None of this is to suggest that digital sampling is stepped and analog sampling is smooth. That's just nonsense and always has been.
- rightbyte 4y ago
  > I would find the first person to draw a "digital sine wave" and handle that problem. If the rise time is way faster then sample period it looks like a "stair step" though. Most audio chips do some fancy interpolation on the other hand.
Maursault 4y ago
Technically, digital can pretty academically produce an analog tape sound and/or a vacuum tube sound. Analog is really just an effect, types of harmonic distortion.
ilyt 4y ago
There is a bit more to that when we get to having to modify or convert audio formats, without "right" algorithms it might introduce some artifacts via aliasing https://www.youtube.com/watch?v=-jCwIsT0X8M https://www.youtube.com/watch?v=-jCwIsT0X8M
- sbaiddn 4y ago
  Too long didn't see the whole thing. Does the video only consider sampling and reconstruction from the samples, or does he talk about quantization noise? That I can perfectly reconstruct a band limited signal from samples taken above the nyquist limit is basic signal math. But any ADC is limited to a finite bit depth and this does introduce errors. Not a signals guy, but I guess this is what the bandwidth theorem is about (snr vs signal power ratio or something). Anyway, Im sure 16bit from my CD is perfect enough for anyone's ears and (obviously?) better than vinyl or cassette. But dammit I like analog music for the same reason I like my mechanical watch - I can really understand the full stack wholly.
KIFulgore 4y ago
Thanks for sharing - I hadn't seen that video. I'm a fan of Technology Connections on YT. I've sent his Nyquist-Shannon video to several friends: https://www.youtube.com/watch?v=pWjdWCePgvA https://www.youtube.com/watch?v=pWjdWCePgvA
rightbyte 4y ago
> It's 2023 and people still think that digital doesn't produce smooth curves Approaching the sample frequency the signal gets quite ugly to watch in an oscilloscope. 22050 Hz is just a triangle wave. Dunno if you can hear signal ugliness though.
- sacrosancty 4y ago
  [dead]

zimpenfish 4y ago

Has anyone ever worked out / quantified what kind of depth difference in a vinyl groove you'd need to beat the CD digital signal for "too subtle to capture"?

TheOtherHobbes 4y ago
You need roughly an extra 60dB of dynamic range to match CD. The largest groove deviation on vinyl - nominal 0dB - is around 23um. To add 60dB you have to multiply by 1000, which gets you 23mm. And increase the thickness correspondingly. This has has tragic consequences for the size and weight of the disk. Although it wouldn't be playable because the stylus would be pulling hundreds of Gs. For the short period for which it survived it would be hot enough to melt the vinyl. (Actually it would probably catch fire.) You can imagine an optical reader - the've been built for for vinyl, but for some reason they never caught on - but if you're going to do that you may as well have a sub-micron digital data stream in a much smaller disk.
- KerrAvon 4y ago
  There’d still be a market for optical vinyl readers — a playback mechanism that didn’t degrade your mint copies of old LPs would be treasured by a lot of people. The old laser turntables never caught on due to the expense — $10,000 a few decades ago, in those dollars at the time — and due to dust and other imperfections causing severe audio glitches that wouldn’t show up or would be less severe with a stylus. These problems should be solvable with current technology, though.
- sbaiddn 4y ago
  The extra information could be stored in the non-audible spectrum of the vinyl. But the reconstruction would be complicated and it would wear out fast. There were some ultrasonics technologies that were aborted when Phillips introduced the CD

function_seven 4y ago

Ha, I knew where that link was going before I clicked it. That is the go-to video to dispel the "stair step" misconception. It worked wonders for me when I first watched it. While many time-machine inventors would go back and kill Hitler, I wouldn't. I would find the first person to draw a "digital sine wave" and handle that problem.

TheOtherHobbes 4y ago
If you really understand digital sampling, there's actually quite a lot wrong in that video. The "16-bit is enough" line is absolutely wrong, because quantisation noise has a very uneven spectrum which is nothing like white noise. It has peaks at certain subdivisions of the sample rate which are quite a way above inaudibility. Which is why dither was invented - to smooth out those peaks. The "44.1kHz is enough" line is also wrong because there's no such thing as a perfect reconstruction filter. (It's mathematically impossible to build a perfect brick wall filter that works in real time.) Real reconstruction filters have trade-offs and the distortions always become more audible and obvious around Nyquist. They're less obvious at higher sample rates. There are also inter-sample peaks which can clip in the reconstruction filter and which are easier to avoid at higher sample rates. Digital also suffers from clock jitter. Early converters were just plain nasty, but these days jitter is barely a problem on cheap converters and not audible at all on pro-grade hardware. None of this is to suggest that digital sampling is stepped and analog sampling is smooth. That's just nonsense and always has been.
rightbyte 4y ago
> I would find the first person to draw a "digital sine wave" and handle that problem. If the rise time is way faster then sample period it looks like a "stair step" though. Most audio chips do some fancy interpolation on the other hand.

Maursault 4y ago

Technically, digital can pretty academically produce an analog tape sound and/or a vacuum tube sound. Analog is really just an effect, types of harmonic distortion.

ilyt 4y ago

There is a bit more to that when we get to having to modify or convert audio formats, without "right" algorithms it might introduce some artifacts via aliasing https://www.youtube.com/watch?v=-jCwIsT0X8M https://www.youtube.com/watch?v=-jCwIsT0X8M

sbaiddn 4y ago
Too long didn't see the whole thing. Does the video only consider sampling and reconstruction from the samples, or does he talk about quantization noise? That I can perfectly reconstruct a band limited signal from samples taken above the nyquist limit is basic signal math. But any ADC is limited to a finite bit depth and this does introduce errors. Not a signals guy, but I guess this is what the bandwidth theorem is about (snr vs signal power ratio or something). Anyway, Im sure 16bit from my CD is perfect enough for anyone's ears and (obviously?) better than vinyl or cassette. But dammit I like analog music for the same reason I like my mechanical watch - I can really understand the full stack wholly.

KIFulgore 4y ago

Thanks for sharing - I hadn't seen that video. I'm a fan of Technology Connections on YT. I've sent his Nyquist-Shannon video to several friends: https://www.youtube.com/watch?v=pWjdWCePgvA https://www.youtube.com/watch?v=pWjdWCePgvA

rightbyte 4y ago

> It's 2023 and people still think that digital doesn't produce smooth curves Approaching the sample frequency the signal gets quite ugly to watch in an oscilloscope. 22050 Hz is just a triangle wave. Dunno if you can hear signal ugliness though.

sacrosancty 4y ago
[dead]