3 ms·

SBC is also not the only BT codec; BT headphones often offer direct mp3 support so that there is no extra loss in quality

esaym 6y ago
The bluetooth stack on linux only supports SBC due to license issues.
- microcolonel 6y ago
  There is a fork of the PulseAudio Bluetooth modules that supports LDAC, AAC, AptX, and AptX-HD. LDAC should be supportable upstream, I think it's coming. On a side note, LDAC is so laughable. I have to imagine the engineers working on it had a lot of laughs. It has all the "high resolution audio" mumbo jumbo that Sony has marketed to audiophools for decades, and it is hilariously inefficient.
ComputerGuru 6y ago
LC3 is the new audio standard for Bluetooth 5.2 and up, but when I read the Bluetooth SIG claims it provides better quality at comparable bitrates to a long list of codecs that ended with "and Opus," I had to laugh and close the tab. For those that don't know, Opus is pretty much the current gold standard for freely available audio formats that are at least partially designed to operate at the very lowest end of the bitrate spectrum while delivering comprehensible audio; unless LC3 is also using SILK but just under a different name, I'd be extremely shocked to find it actually beats Opus.
- marcan_42 6y ago
  "LC3 outperformed Opus at 32 kbps in their tests. But they used an old version (1.1.4) with encoding complexity set to 0." So yeah, it seems they did one test at a low bitrate with an old encoder and poor settings and proclaimed it "better than Opus".
- microcolonel 6y ago
  On that topic, when I get fully set up after my move, I'll have more time to devote to my A2DP Opus mode. I think it's actually not crazy to decode Opus on Bluetooth chipset DSPs, even all the way up to the maximum bitrates. One nice thing about this as well is that adding surround sound modes shouldn't be that hard, I think it would be the first surround sound A2DP configuration. That test is indeed laughable, I read their materials, and it looks like they crippled the Opus encoder, which was already on old release before they used it. Opus 1.3 at an ordinary complexity is doubtless better than LC3, and there are actual encoders and decoders that you can just download and port yourself.

esaym 6y ago

The bluetooth stack on linux only supports SBC due to license issues.

microcolonel 6y ago
There is a fork of the PulseAudio Bluetooth modules that supports LDAC, AAC, AptX, and AptX-HD. LDAC should be supportable upstream, I think it's coming. On a side note, LDAC is so laughable. I have to imagine the engineers working on it had a lot of laughs. It has all the "high resolution audio" mumbo jumbo that Sony has marketed to audiophools for decades, and it is hilariously inefficient.

ComputerGuru 6y ago

LC3 is the new audio standard for Bluetooth 5.2 and up, but when I read the Bluetooth SIG claims it provides better quality at comparable bitrates to a long list of codecs that ended with "and Opus," I had to laugh and close the tab. For those that don't know, Opus is pretty much the current gold standard for freely available audio formats that are at least partially designed to operate at the very lowest end of the bitrate spectrum while delivering comprehensible audio; unless LC3 is also using SILK but just under a different name, I'd be extremely shocked to find it actually beats Opus.

marcan_42 6y ago
"LC3 outperformed Opus at 32 kbps in their tests. But they used an old version (1.1.4) with encoding complexity set to 0." So yeah, it seems they did one test at a low bitrate with an old encoder and poor settings and proclaimed it "better than Opus".
microcolonel 6y ago
On that topic, when I get fully set up after my move, I'll have more time to devote to my A2DP Opus mode. I think it's actually not crazy to decode Opus on Bluetooth chipset DSPs, even all the way up to the maximum bitrates. One nice thing about this as well is that adding surround sound modes shouldn't be that hard, I think it would be the first surround sound A2DP configuration. That test is indeed laughable, I read their materials, and it looks like they crippled the Opus encoder, which was already on old release before they used it. Opus 1.3 at an ordinary complexity is doubtless better than LC3, and there are actual encoders and decoders that you can just download and port yourself.