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> CD audio is perfectly lossless - it encodes the signal that you put in by measuring a voltage 44100 times per second and recording that exactly. When you play

by gspr 4y ago

> CD audio is perfectly lossless - it encodes the signal that you put in by measuring a voltage 44100 times per second and recording that exactly. When you play it back you get exactly the same signal back out. Not at all! CD audio amplitude is quantized to 16 bits, and temporally sampled at 44100 Hz as you say. Certainly very high quality, but there's absolutely a loss (that nobody can really hear).

afiori 4y ago
In terms of media formats lossless in practice means "relative to the input device". Otherwise image formats could not be lossless for the same reasons (at the very least very few of them store the polarity of the light)
- Gordonjcp 4y ago
  Holography stores phase, I guess.
seba_dos1 4y ago
> that nobody can really hear I know that when I was about 10yo, I could hear a tiny suggestion of something audible when I tested my hearing at around 23-24kHz. I guess that if you had some really loud content around these frequencies and had equipment that could reproduce it perfectly, it would be not impossible for it to influence my listening experience those many years ago :)
- Gordonjcp 4y ago
  I used to be able to locate the computer section of WH Smiths or John Menzies in the 1980s and go and play on the ZX Spectrums and Commodore 64s (and other oddities - the one in Arbroath had a couple of Memotech MTX512s!) by hearing the 15kHz scan line whistle from the CRT tellies they used for displays.
- iggldiggl 4y ago
  Although there's also a difference between being able to hear a single tone, and being able to reliably perceive a difference in some more complex bit of noise. Testing with https://www.audiocheck.net/blindtests_frequency.php https://www.audiocheck.net/blindtests_frequency.php, my hearing limit in the white noise case for example is at least 1 to 2 kHz lower than my hearing limit for a single frequency sinus tone.
  - seba_dos1 4y ago
    Oh absolutely, hence the stressed out words in cursive. It isn't going to make any meaningful difference even for a 10yo with perfect hearing - for listening, 44100Hz sample rate is more than enough, and 48000Hz provides large enough headroom to already make any semi-reasonable "audiophile" sleep calm.
CyberDildonics 4y ago
That's not what lossless means here (or anywhere).
- gspr 4y ago
  ?
  - CyberDildonics 4y ago
    ?
    - gspr 4y ago
      What would you say that lossless means, then?
      - CyberDildonics 4y ago
        It isn't me making these definitions. It means that a digital signal is encoded in a way that does not lose information from its original encoding. https://en.wikipedia.org/wiki/Lossless_compression https://en.wikipedia.org/wiki/Lossless_compression https://en.wikipedia.org/wiki/Audio_Lossless_Coding https://en.wikipedia.org/wiki/Audio_Lossless_Coding https://en.wikipedia.org/wiki/Category:Lossless_compression_algorithms https://en.wikipedia.org/wiki/Category:Lossless_compression_... This is very common terminology.
Gordonjcp 4y ago
Lossless to all practical purposes, then. With 16 bits of amplitude quantisation the smallest bit is below the noise floor of all but the quietest possible amplification, and while 44.1kHz isn't a lot it still places the corner frequency of your antialiasing filter comfortably above human hearing. It's got way more audio bandwidth than most of the analogue masters that everyone raves about. No, there's nothing magically audible happening with phase shifts near the steep cutoff of the antialiasing filter that isn't happening with the gentle rolloff of tape, either. Not that you could hear anyway, and even though my hearing is better than most 48-year-old industrial music enthusiasts, not that I could hear either. For cats, even your very best equipment with perfect reproduction sounds like AM radio because their hearing tops out at 80kHz.
- gspr 4y ago
  Absolutely

by gspr 4y ago

afiori 4y ago

In terms of media formats lossless in practice means "relative to the input device". Otherwise image formats could not be lossless for the same reasons (at the very least very few of them store the polarity of the light)

Gordonjcp 4y ago
Holography stores phase, I guess.

seba_dos1 4y ago

> that nobody can really hear I know that when I was about 10yo, I could hear a tiny suggestion of something audible when I tested my hearing at around 23-24kHz. I guess that if you had some really loud content around these frequencies and had equipment that could reproduce it perfectly, it would be not impossible for it to influence my listening experience those many years ago :)

Gordonjcp 4y ago
I used to be able to locate the computer section of WH Smiths or John Menzies in the 1980s and go and play on the ZX Spectrums and Commodore 64s (and other oddities - the one in Arbroath had a couple of Memotech MTX512s!) by hearing the 15kHz scan line whistle from the CRT tellies they used for displays.
iggldiggl 4y ago
Although there's also a difference between being able to hear a single tone, and being able to reliably perceive a difference in some more complex bit of noise. Testing with https://www.audiocheck.net/blindtests_frequency.php https://www.audiocheck.net/blindtests_frequency.php, my hearing limit in the white noise case for example is at least 1 to 2 kHz lower than my hearing limit for a single frequency sinus tone.
- seba_dos1 4y ago
  Oh absolutely, hence the stressed out words in cursive. It isn't going to make any meaningful difference even for a 10yo with perfect hearing - for listening, 44100Hz sample rate is more than enough, and 48000Hz provides large enough headroom to already make any semi-reasonable "audiophile" sleep calm.

CyberDildonics 4y ago

That's not what lossless means here (or anywhere).

gspr 4y ago
?
- CyberDildonics 4y ago
  ?
  - gspr 4y ago
    What would you say that lossless means, then?
    - CyberDildonics 4y ago
      It isn't me making these definitions. It means that a digital signal is encoded in a way that does not lose information from its original encoding. https://en.wikipedia.org/wiki/Lossless_compression https://en.wikipedia.org/wiki/Lossless_compression https://en.wikipedia.org/wiki/Audio_Lossless_Coding https://en.wikipedia.org/wiki/Audio_Lossless_Coding https://en.wikipedia.org/wiki/Category:Lossless_compression_algorithms https://en.wikipedia.org/wiki/Category:Lossless_compression_... This is very common terminology.

Gordonjcp 4y ago

Lossless to all practical purposes, then. With 16 bits of amplitude quantisation the smallest bit is below the noise floor of all but the quietest possible amplification, and while 44.1kHz isn't a lot it still places the corner frequency of your antialiasing filter comfortably above human hearing. It's got way more audio bandwidth than most of the analogue masters that everyone raves about. No, there's nothing magically audible happening with phase shifts near the steep cutoff of the antialiasing filter that isn't happening with the gentle rolloff of tape, either. Not that you could hear anyway, and even though my hearing is better than most 48-year-old industrial music enthusiasts, not that I could hear either. For cats, even your very best equipment with perfect reproduction sounds like AM radio because their hearing tops out at 80kHz.

gspr 4y ago
Absolutely