5 ms·

But do they sound any different?

by gwern 8y ago

jmillikin 8y ago
You're asking the wrong person: I can't reliably tell the difference between FLAC and YouTube. When you've got a .wav file open in a hex editor, it's no longer really about the music itself.
- plg 8y ago
  I bet you could, given good audio equipment (good DAC/amp/speakers or DAC/amp/headphones)
userbinator 8y ago
The article says "there were about 20,000 bytes different betwen each rip", which if it happened in one stretch corresponds to ~113ms of audio. Depending on the exact nature of the error and how it changes the samples, it may be very obvious (e.g. a 113ms burst of silence or static) or inaudible (one different bit in a few hundred thousand --- probably won't even get past the lowpass filtering on the DAC.)
- gwern 8y ago
  That 20,000 bytes might not be a real difference, as I understand OP. It sounds like it's the XOR or Hamming distance, byte or bitwise - in which case you could get very large differences in the number by very small errors like dropping 1 bit (thereby putting all following bits out of alignment) yet the perceptual difference would be unhearable (and maybe not exist at all depending on how the encoding works). eg 0101010 vs 101010. You'd want to calculate some sort of edit distance which takes into account the possible bit flips and burst errors to see how big the real delta is. And of course, as pointed out in the other comments, for all of OP's hard work, there's no way to know which source is right or how many errors remain in his final version.
rsync 8y ago
"But do they sound any different?" As a fellow ripper of physical CDs in 2018, the point is that a correct rip of CDDA from the CD is the one and only way to be sure you won't ever have to rip that music again. Any other file, any other delivery/download mechanism, any other format ... you'll be fooling around with that song again sometime. But not if you have the correct, error free rip of the WAV/PCM from the CD. So it's really not about the sound vs. some other format ...
- wink 8y ago
  As another fellow ripper of physical CDs - is there a good way to check for quality of my rips besides looking at the bitrate and listening to all of them (talking mp3s here, of course)? I'm not interested in perfect lossless quality, but I'm quite sure I should re-rip the CDs I did 10-15 years ago, but for VBR mp3s it's kinda hard to decide what is 'good enough', as compared to say 128kb/s rips - so I'm looking for a scriptable way to give me a rough "keep/maybe/definitely throw away" metric... Rephrasing the question: What are people typically using these days when not going for FLAC? Some of my mp3s are definitely from the "HDD space is expensive" age 15+ years ago...
  - ahje 8y ago
    MP3, with LAME (-q0). A couple of the really old rips used average bit rate instead. Will probably re-rip those at some point, but the rest sounds fine to my ears.
  - namibj 8y ago
    Usually the formats are FLAC, 320, V0, V3.
    - moftz 8y ago
      I've never seen anyone use V3 for VBR rips, usually V2.
- kalleboo 8y ago
  > you'll be fooling around with that song again sometime I've been ripping in AAC 256kbps for 15 years now and have yet to see any reason to revisit any of those CDs. Even if a more efficient encoding mechanism gains mainstream support, I'll just use that for new rips only since storage is cheap enough.
Sir_Cmpwn 8y ago
This matters for long-term music archival when you want to sample it and play with the audio, which could exagerrate the defects as you edit it. We should preserve pristine source material.

But do they sound any different?

by gwern 8y ago

But do they sound any different?

You're asking the wrong person: I can't reliably tell the difference between FLAC and YouTube. When you've got a .wav file open in a hex editor, it's no longer really about the music itself.

plg 8y ago
I bet you could, given good audio equipment (good DAC/amp/speakers or DAC/amp/headphones)

userbinator 8y ago

The article says "there were about 20,000 bytes different betwen each rip", which if it happened in one stretch corresponds to ~113ms of audio. Depending on the exact nature of the error and how it changes the samples, it may be very obvious (e.g. a 113ms burst of silence or static) or inaudible (one different bit in a few hundred thousand --- probably won't even get past the lowpass filtering on the DAC.)

gwern 8y ago
That 20,000 bytes might not be a real difference, as I understand OP. It sounds like it's the XOR or Hamming distance, byte or bitwise - in which case you could get very large differences in the number by very small errors like dropping 1 bit (thereby putting all following bits out of alignment) yet the perceptual difference would be unhearable (and maybe not exist at all depending on how the encoding works). eg 0101010 vs 101010. You'd want to calculate some sort of edit distance which takes into account the possible bit flips and burst errors to see how big the real delta is. And of course, as pointed out in the other comments, for all of OP's hard work, there's no way to know which source is right or how many errors remain in his final version.

rsync 8y ago

"But do they sound any different?" As a fellow ripper of physical CDs in 2018, the point is that a correct rip of CDDA from the CD is the one and only way to be sure you won't ever have to rip that music again. Any other file, any other delivery/download mechanism, any other format ... you'll be fooling around with that song again sometime. But not if you have the correct, error free rip of the WAV/PCM from the CD. So it's really not about the sound vs. some other format ...

wink 8y ago
As another fellow ripper of physical CDs - is there a good way to check for quality of my rips besides looking at the bitrate and listening to all of them (talking mp3s here, of course)? I'm not interested in perfect lossless quality, but I'm quite sure I should re-rip the CDs I did 10-15 years ago, but for VBR mp3s it's kinda hard to decide what is 'good enough', as compared to say 128kb/s rips - so I'm looking for a scriptable way to give me a rough "keep/maybe/definitely throw away" metric... Rephrasing the question: What are people typically using these days when not going for FLAC? Some of my mp3s are definitely from the "HDD space is expensive" age 15+ years ago...
- ahje 8y ago
  MP3, with LAME (-q0). A couple of the really old rips used average bit rate instead. Will probably re-rip those at some point, but the rest sounds fine to my ears.
- namibj 8y ago
  Usually the formats are FLAC, 320, V0, V3.
  - moftz 8y ago
    I've never seen anyone use V3 for VBR rips, usually V2.
kalleboo 8y ago
> you'll be fooling around with that song again sometime I've been ripping in AAC 256kbps for 15 years now and have yet to see any reason to revisit any of those CDs. Even if a more efficient encoding mechanism gains mainstream support, I'll just use that for new rips only since storage is cheap enough.

Sir_Cmpwn 8y ago

This matters for long-term music archival when you want to sample it and play with the audio, which could exagerrate the defects as you edit it. We should preserve pristine source material.