I'd like to get some advice/direction with an issue that I'm having with a new horn....well...new to me. I've been playing a Bach Strad 72* since 1985 (ML .459 bore). I have always loved that horn. But last summer I played a friend's horn that would be considered a "ML+" bore - I think it was a .462. Regardless, I loved the open feel of the horn. I have also had a few small mechanical issues with the Bach, so I thought I'd look around for a horn that had similar characteristics to my Strad (sizzle in the upper register as well as the ability for a big warm sound in the middle and lower when necessary - all great for big band Jazz) - BUT would also have a bit more open blow. Anyway...after playing about a half a dozen horns I found one that I really like - a Kanstul 1600 - the Wayne Bergeron model. It is a used horn - but made in fall of 2008 - so fairly new. It is a .460 bore (not much larger) but has a modified lead pipe which gives it a nice open feel - and can still sizzle in the upper register. Anyway...I love the open feel. It is also a very responsive horn and I think my lower register is clearer, yet didn't take away from the upper register. The bad thing is that the range between D (on the staff) and high A, I am REALLY STRUGGLING with being able to play with accuracy as well as being able to play dolce and lightly while in that range. I thought that I was just going through a tough time, so I pulled out my Bach, and behold, those notes come out again nicely. The big question is...is that ME...do I just need to give it more time and practice?? Or...do you think it is a mechanical thing. I've kept my same mouthpiece (Reeves 41S)...with the same sleeve (4). Should I consider modifying the gap (sleeve), getting a new mouthpiece...or should I just shut up and practice more?? Do you think the horn just isn't right for me?? I'm not sure if I have the patience to break it in more knowing if I just go back to the Bach, I can do those things easily again. Any thoughts?!?? Any help is GREATLY appreciated!