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Comment by goblin89 | Hacker News Reader

> Stop being so paranoid about what you think you can't hear, and enjoy the damn music.

Yes. Do a couple of blind tests with your acoustic system first.

> It's true enough that a properly encoded Ogg file (or MP3, or AAC file) will be indistinguishable from the original at a moderate bitrate.

Disagree. This claim seems to be ungrounded compared with others.

I can believe limitations with bit depth and sampling rate (although I'll take a chance to test myself if I get near good enough acoustic system). However, I definitely could discern in a blind test whether music I listened to was stored using lossy format with reasonable bitrate. It's usually quite audible with rock music that involves cymbals.

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There's a specific "bug" in the mp3 encoding scheme which means that you get a pre-echo effect on fast attack waveforms. It's inherent in the encoding, so it can't be eliminated (although the higher the bitrate, the less obvious it is IIRC). If you how know to listen out for it then you'll spot it immediately.

AAC / Ogg don't have that limitation & at high enough bitrate should be indistinguishable from the source in a blind listening test, as demonstrated in a number of Hydrogen Audio listening tests down the years, unless of course you're using crappy encoders at which point all bets are off...

(Really, LAME is very good indeed these days. I eventually decided that I was going to get with the program and just encode all my CDs (backed up to flac files) as mp3 for portable listening. It's good enough, and I've decided not to listen for the pre-echo artifacts so that I won't notice them :) )

Well, actually it was that long cymbal sounds “fade” quicker and just sound different with lossy music.

IIRC I distinguished an mp3 encoded by iTunes with bit rate 192 or 256 kbps from its original in Apple Lossless (both played on same cheap acoustic system). I probably should test with AAC or Ogg, too. Although I have a feeling that it's pretty much impossible to keep intact those rich in high frequencies cymbals while keeping compact file size.

> I've decided not to listen for the pre-echo artifacts so that I won't notice them :)

You're much better at controlling your mind. =) After I once verified that the difference is audible even on cheap speakers, I can't switch back to lossy formats. It means constant wondering if that how it's supposed to sound or not…

That's, by the way, why Apple's idea of having ‘Mastered for iTunes’ label[0] IMO is worthwhile—at least you can be sure that mastering engineer listened to it this way. =)

[0] http://arstechnica.com/apple/news/2012/02/mastered-for-itune...

Might be interesting to try AAC or Ogg Vorbis & see if they're any better. In these days of ever increasing cheap portable storage carrying a bunch of flacs around isn't quite as nuts as it used to be of course.

(Cymbals seem to be a particular bugbear for mp3 encoding; cymbal-heavy tracks tend to suffer the most from obvious encoding artifacts once you know what to listen for.)

It's certainly true. Ogg is far less audible than mp3 - it's actually very decent at bit rates as low as 64kpbs.

"I distinguished"

Was this in a blind test?

Please refer to my comment above[0]. Yes, it was a blind test. The person helping me might've looked up bit rates, so it was not a double-blind experiment, but I could not (nor did I want to) see what's being played, and relied only on hearing.

[0] http://news.ycombinator.com/item?id=3669893

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