How is the pitch altered on a recorder?

The pitch of a recorder is altered by varying the length of the air column inside the instrument. This can be done by opening and closing the tone holes, which are small holes located along the length of the recorder. When a tone hole is opened, it allows air to escape from the instrument, which shortens the effective length of the air column and raises the pitch. Conversely, when a tone hole is closed, it restricts the flow of air and lengthens the effective length of the air column, which lowers the pitch.

In addition to the tone holes, the pitch of a recorder can also be altered by blowing harder or softer. Blowing harder increases the pressure of the air inside the instrument, which causes the air column to vibrate faster and produce a higher pitch. Conversely, blowing softer decreases the pressure of the air inside the instrument, which causes the air column to vibrate slower and produce a lower pitch.

By combining different fingerings and blowing techniques, a recorder player can produce a wide range of pitches.