What does such a spectrum of an MP3 file mean?

Question

MP3

It seems to bounce up to 18, but a clear cut at 16 is visible. What is it?

Answer 1

This is a completely normal behavior of mp3 encoders (well lame at least) at certain presets/bitrates.
The bottom line is that the encoder cuts high frequencies in order to give the scarce bitrate to more important low and medium ones. But in some places, high frequencies have a sufficiently high amplitude, and it is impossible to fix them at all. The encoder then leaves them as half as possible.
At some lower bitrate, he would cut them off altogether. At a higher level, I would leave it without an intermediate step.
Although, as far as I know, the developers of lame do not recommend completely disabling the low-pass filter, and even at the highest bitrates, "thinning" is done.

Answer 2

Very similar to V2 (VBR 190kbps) from here . Exactly there is a shelf and a cut-off.

Answer 3

Maybe it was already recoded from the clipped one?

Answer 4

Perhaps this is how they mixed it, for example, they stabbed the microphone, which was used to shoot from some combo, at 16 kHz.