Alto clarinet &
Basset horn:

Alto clarinet & Basset horn mouthpieces

All alto clarinets are played with alto clarinet mouthpieces. It is about the size of an alto saxophone mouthpiece but has a cork-covered tenon for the neck of the instrument. You can play alto saxophone reeds on 59 " target="_blank">alto clarinet mouthpieces

82 " target="_blank">Find the right swab
With basset horns that's a different story. Originally the basset horn in F had a smaller bore and was played with a clarinet mouthpiece. The idea was to have an instrument with a clarinet sound but a wider range. The instruments from Steven Fox and Selmer still use the clarinet mouthpiece. These basset horns create a more intimate sound.
Leblanc was the first to build basset horns with a wider bore to get more volume. His instruments used the alto clarinet mouthpiece. They played freer and didn't have the nasal small sound of the smaller bored basset horns. The Leblancs have been the first choice for many players for a very long time.
In mid-1970 Buffet built their first wide bore basset horn. But instead of using an alto clarinet mouthpiece, they modified clarinet mouthpieces, so that their inner bore was wide.