[opus] Impossible two bugs in Opus

[Jan Stary]

On Nov 17 20:37:21, sergeinakamoto at gmail.com wrote:
> Hello. Me again.
> Have you tried to encode piano solo?
> Noticed high bitrate Opus gave?
> Download FLAC and Opus both files,
> new link:
> http://www.filedropper.com/example_3
> FLAC full: 1084 kbps;
> FLAC solo: 465 kbps.
> with --bitrate 160:
> Opus full: 158 kbps;
> Opus solo: 190 kbps.

The two recordings are totaly unrelated.
The fact that it's the same song has nothing to do with it.

Why would a recording of a solo piano necessarily use
a smaller bitrate than a recording of a band?

> And there's also artefact at 15kHz
> which wasn't in the original audio.
> Visible with Spek program.
> Included also Spek spectrogram PNG file
> for Opus solo to see the artefacts.

It is already present in the FLAC file
(see attached spectrogram, obtained with SoX).

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