> I stop being able to tell somewhere around 200 kbit MP3s (with cheap equipment)

Yups. Me too. Even with cheap professional equipment I cannot hear the difference of lossless vs >= 192kbps MP3.

> anything above that is wasted space.

Unless you want to mix/remix/etc. Changing the pitch brings out the artifacts.

I did a blind test with a friend once, 192/320/lossless, and we both could definitely hear which file was 192 - but not which was 320/lossless.

Most of the compression in 320 mp3s is also in areas humans can't hear. I once created a 320 mp3 with a 16kHz cutoff instead of the 20kHz lame uses by default, and to me there was no audible difference - even inverting one and listening to the difference didn't produce anything audible (to me).

Of course nobody uses mp3 anymore, not even iTunes, they encode as 256 aac, which is a far superior codec and near lossless. I doubt anybody can hear the difference between the lossless file and the iTunes file.

> Unless you want to mix/remix/etc. Changing the pitch brings out the artifacts.

Certainly, you probably need lossless if you're going to do any sort of editing.

Lossless, and possibly upsampling before editing, but high end gear probably does that by default. As for bitrate compression, although I have a good musical ear, I can't find any appreciable difference from a high bitrate (320) mp3 and the corresponding lossless track, so no problems using mp3s to listen to music.

I also managed to resample my entire portable playlist (yeah, making mp3s out of mp3s, I know in some circles I could be killed just for thinking about that:*) to overcome that dreadful loudness craze that makes pretty much every track produced in the last 20-25 years destroy your ears if you happen to listen to it just after something 10 years older. Unfortunately all methods to level the tracks (mp3gain, replaygain etc.) don't work properly because they should analyze all tracks dynamic content, not just the average/maximum level, then first adjust their dynamics and later normalize their level. In other words, level compression should be applied more to softer tracks and not the other way around. So I faked a solution to the problem by reconverting my playlist after applying compression to an extremely low threshold, making clear to myself that none of those tracks would ever leave my player. Some sound really horrible, but I spared my ears.

As far as I know, mp3 frames have a "volume" field, which is what mp3gain changes to losslessly change the volume of the entire track. Could you not take advantage of that too?

The problem is the huge difference in dynamics between "old" and "new" recordings (that is, not just their maximum level) which makes really hard if not impossible to have more tracks sounding near the same level.

This Wikipedia article about loudness wars explains the problem in details. https://en.wikipedia.org/wiki/Loudness_war

Not sure you're saving your ears by doing this compared to say, turning the volume down.

You can't 'uncompress' an MP3 back to having the dynamic range it had before.

"You can't 'uncompress' an MP3 back to having the dynamic range it had before."

True. In fact I would rather compress old music to bring it to the same dynamics of the new one, then and only then normalize everything. I know it's almost a crime; I did it just on my player and would never give these tracks to anyone.

Well… maybe some cool AI would help here… We already have it for images!

We can take a jpeg and run it back to RAW?

Because I don't think we can.

>anything above that is wasted space

Having lossless copies is still useful for storage and later transcoding. Even if you can't hear a difference between a 192kbit/s MP3 and a higher bitrate lossless file, you might be able to hear one after reencoding the MP3 using another lossy format.

Yes, I should have said "for casual listening".

Considering the proliferation of music remixing social media services (i.e. Tiktok) and the cheap price of storage, maybe even casual users can benefit from lossless these days.