7 ms·

After reading "How Music Works" by David Byrne, it seem like FLAC is solving the wrong problem. No one needs over 4 billion discrete levels.

_joel 4y ago
Nyquist Shannon theorem, sure. There are situations where you'd use 32bit audio but not for mastered music you'd listen to at home really. Although people still won't believe you, hence the market for thousand dollar cables and other snake oil.
- Night_Thastus 4y ago
  From my understanding, doesn't Nyquist-Shannon assume you take infinite steps to refine the discrete steps into the final waveform? Since real-world DACs don't have infinite taps, either increasing the number of samples per second in the original audio or the number of steps done by the filter will improve how close it gets to the original waveform. Would that apply to the number of bits used to represent the level as well? I thought that was mainly useful to give some additional headroom when editing? (Obviously there's diminishing returns either way)
  - colejohnson66 4y ago
    Nyquist-Shannon simply says that you need 2x the sample rate of the highest frequency to perfectly recreate something. So, to recreate a 20 kHz wave that was sampled at 16 bits, you'd need 40 kHz sample rate. Bump that up to 22.05 kHz (for anti-aliasing) and you get CD audio. The bit depth, OTOH, is your signal-noise ratio (noise floor) when sampling/quantizing said audio. It's unrelated to Nyquist-Shannon. More bits gives you less noise when reproducing it. For CD audio, 16 bits was chosen to give an acceptable SNR of 96 dB. Monty Montgomery (of xipf.org) has a nice YouTube video related to this: https://www.youtube.com/watch?v=cIQ9IXSUzuM https://www.youtube.com/watch?v=cIQ9IXSUzuM
    - Night_Thastus 4y ago
      Yes, you only need that many samples given you know a maximum frequency. But to actually perform the conversion from discrete samples to continuous wave takes infinitely many steps. The number a given DAC actually does varies. Some do hundreds, some thousands, a couple rare (very expensive) ones do 100k or more. That's what I'm saying. Increase the number of samples in the audio itself, and the DAC can get closer to the original.
      - colejohnson66 4y ago
        Except it's not. The video shows that. In the real world, the DAC doesn't immediately jump from code N to N+1; it slides (the "slew rate" of the opamp). More bits just makes the difference between codes N and N+1 smaller; i.e. where it slides to is more accurate to the original. The "stair step" or "straight line" view you get from programs like Audacity is a lie.
        jrmcauliffe 4y ago
        A final low pass filter (tuned to remove anything above half the sample rate) allows the accurate reconstruction of the original analogue waveform from the sampled digital data. ( The vertical 'stair step' of sampled data is very high frequency information which gets removed, 'bending' the output back into it's original shape). The video linked above is well worth a watch.
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atoav 4y ago
I am a recording engineer and I will choose 32 bits over 24 any day when recording. Of course you need the right (exceptionally good!) preamps to even make a difference here, but when you are manipulating audio 32 bits and upwards (for summing) are the default (for a reason). Having something to store those files with a little bit of lossless compression is a welcome addition
- michaelwww 4y ago
  > I will choose 32 bits over 24 any day why?
  - Blueskytech 4y ago
    Because if the recording goes past the clipping range for digital audio it still records the data and preserves it. 32bit recording has serious advantages because it’s much easier to record a hot input because digital clipping is not possible. You just need to pull the volume down on the recorded clip after the fact and there is no clipping.
- squeaky-clean 4y ago
  It's very unlikely your audio interface can actually record at 32 bit resolution. https://www.mojo-audio.com/blog/the-24bit-delusion/ https://www.mojo-audio.com/blog/the-24bit-delusion/ 32bit or more makes sense for dsp and summing, and non-musical data storage. But your I/O is most likely not giving 32 bits
  - jrajav 4y ago
    32-bit is common in field recordings, like with a Zoom (and there's reason to believe they can legitimately take advantage of it).
    - deleted 4y ago
      [deleted]
    - squeaky-clean 4y ago
colejohnson66 4y ago
You're correct; lossless formats aren't needed by the average consumer. But the problem they solve is a very real thing. Think of the difference between a repeatedly edited JPG vs. a repeatedly edited PNG. Every save of the JPG destroys information irretrievably, whereas every save of the PNG keeps it all. It's the same with MP3 vs. FLAC: MP3 throws away information each export, but FLAC doesn't. For an example, music artists/producers can't afford to lose information when they "bounce" a track. FLAC solves that. "People" don't need lossless, but for those that do, it's great.
- pwiecz 4y ago
  "People" don't need just lossless, they need The Beatles to release all of their pre-master tracks to be released in lossless format, so they of them can create their own remastered versions of a the tracks.
- michaelwww 4y ago
  16 bit is not enough?
  - deleted 4y ago
    [deleted]
  - pavon 4y ago
    No, if you want your final output to be 16-bit (eg CD quality), then you need more bits to work with when mixing. Each operation you perform will be requantized (rounded) to 16-bit resolution adding a bit of noise each time, until eventually the lower 4 bits (for example) are nothing but noise, and your signal is effectively only 12 bits. One the other hand if you did that mixing at 24-bit resolution, then you still have 20 bits of good data remaining, you throw away the bottom 4, and have nice clean 16-bit data to distribute. 32-bit integer is overkill in most situations, which is why it wasn't implemented for so long. 32-bit float is used a lot because it has 24-bits of resolution, but also has a huge scaling range, so you don't have to worry about clipping during intermediate operations, just at the end.
- squeaky-clean 4y ago
adgjlsfhk1 4y ago
There are definitely scientific uses that might want to (ab)use FLAC to store sound-like data that would benefit from 32 bit.
mmastrac 4y ago
There's a real use case for storing original tracks and masters in 32-bit and down-sampling for consumer use.
tombert 4y ago
While I doubt that human ears need 4 billion discrete levels, I think it's important for archival purposes.
- klodolph 4y ago
  Is it? What is your reasoning? And why would you pick 32-bit, instead of 24-bit or 64-bit or something else? Actual audio equipment has a noise floor. The encoding depth you use also has a noise floor. If the noise floor of the encoding is far below the noise floor of the signal, then it won't be perceptible. So you choose to put your noise floor at some amount below the existing noise floor. Not infinitely below, because that would require infinite bits. This is the reasoning you'd use for 24-bit audio, which has a very comfortable noise floor of -144 dB, which leaves a large margin even for extreme low-noise professional equipment (you might see -120 dB ish for extremely good equipment). At 24-bit, even passive components like transformers and resistors are contributing measurable amounts of noise. The reason you might pick 32-bit in practice is so that you can have lots of headroom for some DSP algorithm, or do lots of sums of different signals without accumulating quantization error. The final "archive" file will still have worse than 24-bit precision.
  - tombert 4y ago
    Fair enough! That's what I get for commenting on something I'm not as familiar enough with as I should be.
matheusmoreira 4y ago
How do you know no one needs it for anything? How do you know no one will ever need it in the future? It's not possible to know that. All we can do is capture the real world data with as much quality and precision as possible.
jlouis 4y ago
I don't think it's for storing music.
navjack27 4y ago
I got this one "remaster" of an album that I like that I've been working on that the 32-bit version that 100% definitely goes over 0 DB just happens to sound a whole lot better when I don't correct for that so on occasion I like to load up that album in Ableton live and listen to it exactly like that.

_joel 4y ago

Nyquist Shannon theorem, sure. There are situations where you'd use 32bit audio but not for mastered music you'd listen to at home really. Although people still won't believe you, hence the market for thousand dollar cables and other snake oil.

Night_Thastus 4y ago
From my understanding, doesn't Nyquist-Shannon assume you take infinite steps to refine the discrete steps into the final waveform? Since real-world DACs don't have infinite taps, either increasing the number of samples per second in the original audio or the number of steps done by the filter will improve how close it gets to the original waveform. Would that apply to the number of bits used to represent the level as well? I thought that was mainly useful to give some additional headroom when editing? (Obviously there's diminishing returns either way)
- colejohnson66 4y ago
  Nyquist-Shannon simply says that you need 2x the sample rate of the highest frequency to perfectly recreate something. So, to recreate a 20 kHz wave that was sampled at 16 bits, you'd need 40 kHz sample rate. Bump that up to 22.05 kHz (for anti-aliasing) and you get CD audio. The bit depth, OTOH, is your signal-noise ratio (noise floor) when sampling/quantizing said audio. It's unrelated to Nyquist-Shannon. More bits gives you less noise when reproducing it. For CD audio, 16 bits was chosen to give an acceptable SNR of 96 dB. Monty Montgomery (of xipf.org) has a nice YouTube video related to this: https://www.youtube.com/watch?v=cIQ9IXSUzuM https://www.youtube.com/watch?v=cIQ9IXSUzuM
  - Night_Thastus 4y ago
    Yes, you only need that many samples given you know a maximum frequency. But to actually perform the conversion from discrete samples to continuous wave takes infinitely many steps. The number a given DAC actually does varies. Some do hundreds, some thousands, a couple rare (very expensive) ones do 100k or more. That's what I'm saying. Increase the number of samples in the audio itself, and the DAC can get closer to the original.
    - colejohnson66 4y ago
      Except it's not. The video shows that. In the real world, the DAC doesn't immediately jump from code N to N+1; it slides (the "slew rate" of the opamp). More bits just makes the difference between codes N and N+1 smaller; i.e. where it slides to is more accurate to the original. The "stair step" or "straight line" view you get from programs like Audacity is a lie.
      - jrmcauliffe 4y ago
        A final low pass filter (tuned to remove anything above half the sample rate) allows the accurate reconstruction of the original analogue waveform from the sampled digital data. ( The vertical 'stair step' of sampled data is very high frequency information which gets removed, 'bending' the output back into it's original shape). The video linked above is well worth a watch.
- deleted 4y ago
  [deleted]
- deleted 4y ago
  [deleted]

atoav 4y ago

I am a recording engineer and I will choose 32 bits over 24 any day when recording. Of course you need the right (exceptionally good!) preamps to even make a difference here, but when you are manipulating audio 32 bits and upwards (for summing) are the default (for a reason). Having something to store those files with a little bit of lossless compression is a welcome addition

michaelwww 4y ago
> I will choose 32 bits over 24 any day why?
- Blueskytech 4y ago
  Because if the recording goes past the clipping range for digital audio it still records the data and preserves it. 32bit recording has serious advantages because it’s much easier to record a hot input because digital clipping is not possible. You just need to pull the volume down on the recorded clip after the fact and there is no clipping.
squeaky-clean 4y ago
It's very unlikely your audio interface can actually record at 32 bit resolution. https://www.mojo-audio.com/blog/the-24bit-delusion/ https://www.mojo-audio.com/blog/the-24bit-delusion/ 32bit or more makes sense for dsp and summing, and non-musical data storage. But your I/O is most likely not giving 32 bits
- jrajav 4y ago
  32-bit is common in field recordings, like with a Zoom (and there's reason to believe they can legitimately take advantage of it).
  - deleted 4y ago
    [deleted]
  - squeaky-clean 4y ago

colejohnson66 4y ago

You're correct; lossless formats aren't needed by the average consumer. But the problem they solve is a very real thing. Think of the difference between a repeatedly edited JPG vs. a repeatedly edited PNG. Every save of the JPG destroys information irretrievably, whereas every save of the PNG keeps it all. It's the same with MP3 vs. FLAC: MP3 throws away information each export, but FLAC doesn't. For an example, music artists/producers can't afford to lose information when they "bounce" a track. FLAC solves that. "People" don't need lossless, but for those that do, it's great.

pwiecz 4y ago
"People" don't need just lossless, they need The Beatles to release all of their pre-master tracks to be released in lossless format, so they of them can create their own remastered versions of a the tracks.
michaelwww 4y ago
16 bit is not enough?
- deleted 4y ago
  [deleted]
- pavon 4y ago
  No, if you want your final output to be 16-bit (eg CD quality), then you need more bits to work with when mixing. Each operation you perform will be requantized (rounded) to 16-bit resolution adding a bit of noise each time, until eventually the lower 4 bits (for example) are nothing but noise, and your signal is effectively only 12 bits. One the other hand if you did that mixing at 24-bit resolution, then you still have 20 bits of good data remaining, you throw away the bottom 4, and have nice clean 16-bit data to distribute. 32-bit integer is overkill in most situations, which is why it wasn't implemented for so long. 32-bit float is used a lot because it has 24-bits of resolution, but also has a huge scaling range, so you don't have to worry about clipping during intermediate operations, just at the end.
squeaky-clean 4y ago

adgjlsfhk1 4y ago

There are definitely scientific uses that might want to (ab)use FLAC to store sound-like data that would benefit from 32 bit.

mmastrac 4y ago

There's a real use case for storing original tracks and masters in 32-bit and down-sampling for consumer use.

tombert 4y ago

While I doubt that human ears need 4 billion discrete levels, I think it's important for archival purposes.

klodolph 4y ago
Is it? What is your reasoning? And why would you pick 32-bit, instead of 24-bit or 64-bit or something else? Actual audio equipment has a noise floor. The encoding depth you use also has a noise floor. If the noise floor of the encoding is far below the noise floor of the signal, then it won't be perceptible. So you choose to put your noise floor at some amount below the existing noise floor. Not infinitely below, because that would require infinite bits. This is the reasoning you'd use for 24-bit audio, which has a very comfortable noise floor of -144 dB, which leaves a large margin even for extreme low-noise professional equipment (you might see -120 dB ish for extremely good equipment). At 24-bit, even passive components like transformers and resistors are contributing measurable amounts of noise. The reason you might pick 32-bit in practice is so that you can have lots of headroom for some DSP algorithm, or do lots of sums of different signals without accumulating quantization error. The final "archive" file will still have worse than 24-bit precision.
- tombert 4y ago
  Fair enough! That's what I get for commenting on something I'm not as familiar enough with as I should be.

matheusmoreira 4y ago

How do you know no one needs it for anything? How do you know no one will ever need it in the future? It's not possible to know that. All we can do is capture the real world data with as much quality and precision as possible.

jlouis 4y ago

I don't think it's for storing music.

navjack27 4y ago

I got this one "remaster" of an album that I like that I've been working on that the 32-bit version that 100% definitely goes over 0 DB just happens to sound a whole lot better when I don't correct for that so on occasion I like to load up that album in Ableton live and listen to it exactly like that.