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I believe Fraunhofver did a pretty rigorous scientific test that established the CD transparency quality to be around 256kbps mp3. I don't dispute or doubt that

I believe Fraunhofver did a pretty rigorous scientific test that established the CD transparency quality to be around 256kbps mp3. I don't dispute or doubt that. However, obvious encoding artifacts abound on Spotify. Do I have a superhuman hearing? Probably not. My hypothesis is that not everyone authors lossy files as meticulously as Fraunhofver. Also, the performance of mp3 depends on a highly linear and faithful reproduction after decoding. Mp3 is painfully obvious on crappy, processed-to-hell speaker systems like the iMac. I think the real question is, why bother with lossy codecs? FLAC streams are lightweight by today's standards, and it's just so much simpler.

KozmoNau7 5y ago
Spotify doesn't use MP3, though. So if you're hearing MP3-specific artifacts (pre-echo, washy "underwater" cymbals), those are probably the result of bad mastering or perhaps using MP3-encoded samples in some tracks. I hear this on some lossless tracks I have, unfortunately if the source material is flawed, there's nothing you can do. Spotify uses Ogg Vorbis, except the lowest bitrate on mobile, which is HE-ACCv2, and on Chromecast/similar devices, which get AAC (because they can't natively decode Ogg Vorbis). It is a significantly better codec than MP3, and doesn't suffer from the pre-echo, washy cymbals and badly-encoded high frequencies. At least not until you severely decrease the bitrate.
- CuriousSkeptic 5y ago
  I did some test with ogg vorbis a while back. I think it was q4 vs q5 that was my limit. What struck me though was that I couldn’t tell which was “better”. In the track there was a section where the background drumming on one setting sounded like aluminum drum sticks while the other like wooden drumstick. Very subtle effect, and took some intense concentration to pick out.
- vnorilo 5y ago
  That is true of course, although the more modern codecs most significantly outperform mp3 at lower bitrates. At 256kbps mp3 should be enough, and iirc Spotify offers 320kbps ogg in hifi mode (not sure, I mostly don't ever use it unless someone links something) which should also be enough. The most common problem is when the master is hot and encodes clipped waveforms. It sounds even stranger on lossy. In fact I'm not sure if the codecs' filter banks still have perfect reconstruction in this case or if it's just a borked master. In any case, it always tends to be quite clear when I switch between lossy and lossless on Tidal. Anyway, it's complicated and brittle, and lossless 44/16 is only something like 2x bitrate and bit-perfect (so you can write proper regression tests for codecs very easily) shrug, I think I'll go that route. disclaimer: occasionally get paid for mastering music, so I'm wired to prefer simplicity, transparency and don't mind some redundancy in ensuring signal integrity.
crazygringo 5y ago
> Mp3 is painfully obvious on crappy, processed-to-hell speaker systems like the iMac. I didn't know that was the case. Do you know why that somehow accentuates MP3 artifacts? It's not obvious to me why it would, since all the processing iMac speakers might perform is high-quality (no recompression involved). I mean, obviously the iMac isn't going to improve the MP3, it just tries to improve the speakers. But why would that make artifacts more noticeable? If anything, don't "crappy" speakers hide MP3 artifacts, because they're not good enough to expose them?
- vnorilo 5y ago
  Mp3 relies on the fact that loud sounds mask spectrally and temporally adjacent softer sounds (psychoacoustic masking) and allows the noise floor to rise for some bands in such conditions to reduce the required number of bits to encode the band signal. Now if the masking sound disappears or changes, the crap is no longer masked. In other words the psychoacoustic principles work only when we don't alter the signal too much after the codec. Many diminutive speakers make use of techniques like multiband compression (dynamics, not entropy) to produce "larger" sound. That wreaks havoc on the psychoacoustic model of lossy codecs.
  - deleted 5y ago
    [deleted]

KozmoNau7 5y ago

Spotify doesn't use MP3, though. So if you're hearing MP3-specific artifacts (pre-echo, washy "underwater" cymbals), those are probably the result of bad mastering or perhaps using MP3-encoded samples in some tracks. I hear this on some lossless tracks I have, unfortunately if the source material is flawed, there's nothing you can do. Spotify uses Ogg Vorbis, except the lowest bitrate on mobile, which is HE-ACCv2, and on Chromecast/similar devices, which get AAC (because they can't natively decode Ogg Vorbis). It is a significantly better codec than MP3, and doesn't suffer from the pre-echo, washy cymbals and badly-encoded high frequencies. At least not until you severely decrease the bitrate.

CuriousSkeptic 5y ago
I did some test with ogg vorbis a while back. I think it was q4 vs q5 that was my limit. What struck me though was that I couldn’t tell which was “better”. In the track there was a section where the background drumming on one setting sounded like aluminum drum sticks while the other like wooden drumstick. Very subtle effect, and took some intense concentration to pick out.
vnorilo 5y ago
That is true of course, although the more modern codecs most significantly outperform mp3 at lower bitrates. At 256kbps mp3 should be enough, and iirc Spotify offers 320kbps ogg in hifi mode (not sure, I mostly don't ever use it unless someone links something) which should also be enough. The most common problem is when the master is hot and encodes clipped waveforms. It sounds even stranger on lossy. In fact I'm not sure if the codecs' filter banks still have perfect reconstruction in this case or if it's just a borked master. In any case, it always tends to be quite clear when I switch between lossy and lossless on Tidal. Anyway, it's complicated and brittle, and lossless 44/16 is only something like 2x bitrate and bit-perfect (so you can write proper regression tests for codecs very easily) shrug, I think I'll go that route. disclaimer: occasionally get paid for mastering music, so I'm wired to prefer simplicity, transparency and don't mind some redundancy in ensuring signal integrity.

crazygringo 5y ago

> Mp3 is painfully obvious on crappy, processed-to-hell speaker systems like the iMac. I didn't know that was the case. Do you know why that somehow accentuates MP3 artifacts? It's not obvious to me why it would, since all the processing iMac speakers might perform is high-quality (no recompression involved). I mean, obviously the iMac isn't going to improve the MP3, it just tries to improve the speakers. But why would that make artifacts more noticeable? If anything, don't "crappy" speakers hide MP3 artifacts, because they're not good enough to expose them?

vnorilo 5y ago
Mp3 relies on the fact that loud sounds mask spectrally and temporally adjacent softer sounds (psychoacoustic masking) and allows the noise floor to rise for some bands in such conditions to reduce the required number of bits to encode the band signal. Now if the masking sound disappears or changes, the crap is no longer masked. In other words the psychoacoustic principles work only when we don't alter the signal too much after the codec. Many diminutive speakers make use of techniques like multiband compression (dynamics, not entropy) to produce "larger" sound. That wreaks havoc on the psychoacoustic model of lossy codecs.
- deleted 5y ago
  [deleted]