old (Conn) baritone horns are known to have quirky intonation and this is a common problem , In fact I had the same with a similar horn.
Intonation improved with a better embouchure (tightening of the embouchure going up shows dramatically on baritone) and a older style, big Chamber Mouthpiece.
Intonation improved with a better embouchure (tightening of the embouchure going up shows dramatically on baritone) and a older style, big Chamber Mouthpiece.