If any of you are having trouble playing in the upper range, I'd recommend you do what I did. Get a copy of Jeff Smiley's book, The Balanced Embouchure. Read it & do it. It works. I have a great range now, whereas before his book, I was stuck below the top of the staff for about 3 years. The Trumpet Herald Forum has a group dedicated especially to help people learn the balanced embouchure techniques. The book is written for trumpet, but it works great for horn, too.

Valerie in Tacoma, WA