What is harmonica full valving and half valving?

Full valving and half valving are techniques used in harmonica design to control airflow and sound production. Full valving involves sealing the harmonica's chambers completely with valves, allowing for greater control over the airflow and enhancing the instrument's ability to produce a wider range of tones. Half valving, on the other hand, uses partial sealing, which creates a more nuanced sound and allows for easier bending of notes. These techniques influence playability and tonal characteristics, catering to different playing styles.