Before each playing with some instrument or orchestra, or playing in the orchestra, it is necessary to adjust the intonation. This is called tuning.
Warmed (played) clarinet is tuned to the chamber tone a1 (440 Hz).
Here’s how it works in practice: after the piano (accompaniment) has played the chamber tone a1, the clarinet plays the same tone that sounds like a1, written b1.
- If necessary to lower the tone (intonation)of the clarinet – pull the barrel out.
- If necessary to raise the tone – push the barrel in (see picture left).
Since the clarinet is cold in cold rooms, its intonation is low and it is necessary to raise it by pushing the barrel in.
On the contrary, in warm rooms the clarinet is warm, its intonation is high and it is necessary to lower it by pulling the barrel out.
Taken from my book
I Am Studying Clarinet II