I noticed that IB instruments don't always sound very good in mono and have a lot of phase cancelation issues, and I couldn't figure out why. I thought maybe it was the instrument's impulse reverbs doing it, but even after disabling them in kontakt, I was still having mono phasing issues with the raw instruments.
So I looked at the raw waveforms themselves in the sample directory. Oddly enough, a lot of these waveforms, even though technically they're properly stereo correlated for the most part, seem to lose a lot of upper frequency information when they're converted to mono, and thus are not very mono friendly. Rather than play the waveforms in here and destroy everyone's ears, I'll just show a raw IB Trumpet 1 playing an F scale as an example.
Here it is normally in the Bersa hall:
Shared with Dropbox
www.dropbox.com
And Bersa mono:
Shared with Dropbox
www.dropbox.com
You can already hear the phasing going on in mono, so here is the raw trumpet with no impulses on, in stereo (!!! VOLUME WARNING!!!!!):
Shared with Dropbox
www.dropbox.com
and mono:
Shared with Dropbox
www.dropbox.com
As you can hear, this trumpet sounds nice and full in stereo, but in mono it loses a lot of the high end, and what's left is kind of smeared and odd sounding, kind of like the player is waving their hand around in front of the bell or something. It gets a very pronounced dip in mono around 7k, especially when played loudly, and on certain notes.
True, some of this is inevitable when summing to mono, but this is usually minimized by careful recording and mixing. This explains why IB instruments don't always "sit well" in mono. Hopefully this can be fixed, because otherwise I absolutely love these samples. Just a bit of a monkey's paw right now.