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by bityard 585 days ago
Ability to tell MP3 from the original source was always dependent on encoder quality, bitrate, and the source material. In the mid 2000's, I tried to encode all of my music as MP3. Most of it sounded just fine because pop/rock/alt/etc are busy and "noisy" by design. But some songs (particularly with few instruments, high dynamic range, and female vocals) were just awful no matter how high I cranked the bitrate. And I'm not even an "audiophile," whatever that means these days.

No doubt encoders and the codecs themselves have improved vastly since then. It would be interesting to see if I could tell the difference in a double-blind test today.

2 comments

I find generic ABX tests not great, personally, because I generally don’t know what to be listening for. However, with songs I’ve listened to lossless my whole life, it’s much easier to spot encoding failures - an intuitive “wait, that cymbal crash sounded different” or “that multi-instrument harmonic should be cleaner/dirtier.”

That being said, 320Kbps AAC encoded by Core Audio I’ve found to be pretty much transparent with anything I’ve thrown at it. Anything less than that (256Kbps AAC, 320Kbps MP3, etc) I can ABX sometimes, as long as I’m familiar with the source material, and usually only with quality headphones. Although no streaming services provide that, so I’m stuck with ALAC through Apple Music for streaming (which is more convenient than my old solution, which was transcoding and transferring to an iPod ~20k songs selected from ~90k in my library based on a variety of rules than never gave me the song I’m looking for). And really, ~900Kbps lossless is pretty easy to justify these days with 5G data speeds and generally much higher data transfer limits.

The other downside to storing losing encodings these days is the fact that almost everyone uses Bluetooth for their listening, which is an additional lossy encoding. While 256Kbps AAC/320Kbps MP3 might be transparent in some cases, when it’s re-encoded it very rarely is (in my experience)

iirc there's "easy" (though i don't know them) tests to validate if the signal is lossless or not. When played over speakers for humans, at least.

I always intend to figure out how that works, because i don't feel a lot of audiophiles are actually speaking truth in many cases lol. Still, i don't know - i can't remember my sources to figure it out for myself :/