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Comment by ordu | Hacker News Reader

At high bitrates maybe mp3 has the same heard quality. But mp3 has his artifacts, and the problem is if you heard them once, you couldn't stop youself from hearing them every time. It's like interlacing in movies or bugs at borders of contrasting areas of picture in jpeg. And yes, this can be proved by double-blind experiment at least for 128 kbit/s mp3. With 192 kbit/s, I believe, you can hear artifacts also, but you would need some special training for it. So with 192 kbit/s solution is simple: just do not teach youself to hear artifacts. With lower bitrates it's not so simple.

As for me, flac is better for storing sounds. Stored flac has no artifacts (if obtained without them), I can recode it to mp3, vorbis, opus or something else, and get artifacts from that codec, but not artifacts from mp3 plus artifacts from that codec.

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Can you give some sources? What are these artifacts you talk about?

And even assuming that it's audible at 192kbit/s with a decent encoder, why not just use 320kbit/s MP3 which are still significantly smaller than lossless?

16bit lossless audio is great for producers, you have a lot of headroom for messing with it, re-encoding it, twisting it, amplifying it, mixing it etc... But if you're just archiving public releases for "consumption" it's completely overkill.

>It's like interlacing in movies or bugs at borders of contrasting areas of picture in jpeg

In what way? Interlacing is completely irrelevant in the context of audio.

I'm sorry if I come off as adversarial but it's a pet peeve of mine. The maths and physics behind signal processing are very well understood, if some algorithm induces a signal degradation in the audible spectrum it should be trivial to show it objectively with the right measuring equipment and/or the right mathematical equation.

https://en.wikipedia.org/wiki/Pre-echo is the usual example. I did hear it in that audio example on Wikipedia, but I doubt I'd hear it under realistic circumstances.

> What are these artifacts you talk about?

Splash cymbals in particular sound terrible (or noticeably degraded) on low bitrate stereo MP3s (ie 128kbit/s). Some early encoders actually did a lowpass filter to eliminate frequencies above 16kHz, to mask the 'watery' high-frequency warble (see [1]). Note how even the Fraunhofer codec differs a lot at high-frequencies in the charts on that link.

Some of it is still noticeable even in lower bitrate AAC. I've got U2's Pop album on CD from 1997 (coincidentally the first album to be leaked as MP3 [2]), and even at 128kbps iTunes AAC the cymbals just don't sound right on 'Gone'. They're watery, like an audio version of a badly compressed JPG. I keep meaning to re-rip it at higher bitrate.

[1] http://archive.arstechnica.com/wankerdesk/1q00/mp3/mp3-3.htm...

[2] http://pitchfork.com/thepitch/652-a-history-of-digital-album...

If I remember correctly, some of it came down to encoder settings as well. Joint stereo, for example, always sounded janky at all bitrates. CBR vs VBR also made a difference. Also, the quality of the source was a factor. A low quality source that was already kind of lossy would sound much worse than the source itself when encoded at lower bitrates.

This. Maybe people have different hearing skills also. But I can definitely hear the artifacts in MP3s, like hihats getting muffled and the deep base getting lost in the sea of MP3 compression.

With good headphones (I'm talking 200+ euros class headphones for example) there is a certain difference between even a 320 kpbs MP3 vs a 128 AAC.

AAC or OGG for example just has better usualy clarity in the sound, the bass is clearer and more distinct and the hihats and other hi sounds aren't muffled in the background or don't lose their clarity like they do with MP3s.

And like the parent wrote, once you have heard those 'signature losses' of the mp3 codec, it's very hard not to notice them.

320 mp3's sound just like .wav's to me. I have a middle of the road studio at home, and they sound great on my 8" monitors. I'll play back to back albums in wav, then mp3. Nothing sticks out at me.

who uses 128 kbit/s mp3 these days? the lowest I find are 192

I have a ton of CDs I ripped to 128 kbit a long time ago, back when I couldn't afford the space for anything larger. Honestly, at my age, with only a few exceptions, I don't really notice anything.

Still, when I get new stuff, or rip now, I try to do it at least at 192 or 320, since space isn't an issue any longer.

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