[vorbis] Encoder oddity?

[Robert Adolfsson]

Hi.

I can only say kudos to the Vorbis team!
The v1.0 encoder is really great! It's superior to anything I've tried
before and especially at low bitrates.
I do have one question, probably to Monty.

I have one song, Dire Straits - Brothers in Arms, that I think (subjectivly)
don't encode as good
as other tunes I tried so far.

Problem 1: When encoding at low bitrates, q2 and below, the saxofone at
~1:08-> exhibits a tremolo
style artifact when it should be very smooth. It's very apparent
when -1<=q<1. When q is increased
above 2 it's very hard to notice this, but it's seems to correleted with the
hithat and cymbal.

Problem 2: At roughly the same point when encoding with q4 I can't say that
there is anything wrong
with the encoding of the saxofone, but I still think there is something odd
going on. It feels like there
is too much edge to the instruments and the highs in the hihat and cymbals
are somewhat harsh to the point that
I feel "listening fatigue" after just listening for a couple of minutes. My
subjective listening tells me that
the hihat is too pronounced/realtivly too loud/too metallic compared to the
original and I sense that it's
also coloring the other instruments.

Could there be a connection between the two behaviours I described?

Maybe this is to be expected when compressing with Vorbis 1.0 or I'm hearing
something that isn't there,
atleast at q4, but I really feel alot less strained when listening to the
original/other compressed material.
The reason I posted about this is, as I said in the beginning, because I
feel this specific tune is encoding
worse than other material I have including several songs from the same
album.

The song is taken from:
Artist: Dire Straits
Album: Brothers in Arms
Song: Brothers in Arms
Label/Nr: Vertigo 824 499-2

Keep up the good work and congrats to whole team!

/Robert

<p><p>--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'vorbis-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.