> This is largely because MP3 is a crappy, old format. Try high-bitrate Opus on most samples and you're a lot less likely to get above-chance results on an ABX

> This is largely because MP3 is a crappy, old format. Try high-bitrate Opus on most samples and you're a lot less likely to get above-chance results on an ABX test, pretty much ever, at high bitrates. On the whole your comment is great, but I think this point might be revealing of either your age or the last time your looked at mp3 encoders. LAME has been great for at least a decade now. Other than (possibly) extremely rare killer samples, you're unlikely to be able to ABX a LAME encoded track at 256 Kbps. I certainly can't, and I have pretty decent gear and have been listening to (and working on) music for a very long time. Back in the 90s, all mp3 encoders were shit. Xiph's Monty, in the post you link, mentions being able to distinguish between them using only their results as a party trick. Even in the early 2000s you needed 256-320 Kbps to have a shot at transparency. But now, most music is transparent at `lame -V2` settings, which gives approximately 192 Kbps results. I can still ABX a very small number of songs (last I tested), but even these go away by `lame -V0`, which is the highest quality VBR mode. HydrogenAudio, a trustworthy source as far as "audiophile" claims go, says that anything from `-V0 to -V3` should be transparent under most conditions. https://wiki.hydrogenaud.io/index.php/LAME https://wiki.hydrogenaud.io/index.php/LAME AAC and Vorbis are certainly better codecs, achieving transparency most of the time at closer to 160 Kbps. Opus is even better. I've never been able to ABX a 128 Kbps track, and music sounds great even at 96 Kbps (for stereo!). There are supposed to be killer samples for all four, forcing them to require a higher bitrate to achieve transparency, but interest in finding these seems to have dropped.