It sometimes happens that in certain themes, you are forced to play a A flat with a bombard.
This is always a somewhat delicate exercise since you will have to perform what is called a fork with your middle finger and thumb.
For beginners, the difficulty comes from the fact that this position unbalances the bombard when alternating fingers. In fact, we move from a position where the index finger and thumb allow perfect balance to a position where the index finger is raised and the middle finger placed. It is at this moment that the pressure of the fingers is modified and the hand is unbalanced.
At that moment, unconsciously, we change the air pressure even though we must remain truly constant. It is therefore essential to respect the rules for holding the reed and the lip forceps. The breath must remain regular so that the pressure on the reed is constant.
So when you use the fork at the top of the bombarde, think about your fingers but above all and above all about your breath and your pliers.
To find out everything in detail, find Philippe Janvier's course:
https://www.breizh-music.bzh/video/plinn-utilization-du-lab-cours-musique-bretonne,44
