Author: Ken Lagace
Date: 2019-04-17 17:55
Many things may be causing this - and students start to disguise it by not blowing through the break to prevent the squeak. BAD!
It can be caused by sloppy finger covering, poor embouchure, or other causes.
By the way, there are no squeaks on a clarinet, they are overtones playing when you don't them.
I would suggest starting and perfecting A to B slurs, G to B etc.
And, by the way, the lower register is called chalameau after the oldest ancestor of the clarinet.
When a register key was added around 1700 by Denner allowed playing a higher register, (actually the second overtone in the overtone series), it was called the clarion register. Above the C above the staff, the higher notes are called the altissimo register which goes to the 'real' high 'C' and and even above that C. These notes are what sometimes sound when something in the sound production is awry.
So the real high C is really an octave and a half above the staff.
If I was sitting beside you I would show you my REALM sound production method. It helps to find the best Reed-Embouchure-Air-Ligature-Mouthpiece combination to make a proper clarinet sound. And then, only get those high notes when you want to!