Third partial also, but not as bad as 6th partial. 5th partial tends to be a bit flat.

Here they are though not related to Conn-Selmer. Just a side thread.

1st partial - generally flat, hard to center
2nd partial - in tune
3rd partial - slightly sharp
4th partial - in tune
5th partial - slightly flat
6th partial - Sharp
7th partial - extremely flat
8th partial - in tune
9th partial - sharp
10th partial - flat
11th partial - VERY flat
12th partial - Sharp