About clarinet mouthpieces

Mouthpiece and the reed make the clarinet sound. Reed is attached to mouthpiece by ligature.

When musician  blows into the clarinet, reed vibrates and that makes the sound. Mouthpiece defines the sound and ligature must be at the right place, otherwise the reed has problems vibrating.

The top of the mouthpiece (clarinet players put in their mouth) and the top of the reed are 1mm apart.

The difference in this distance must be very exact. This distance is approximately between 1.000mm to 1.040mm. There is a lot of different mouthpieces on the market and the technology  must be very precise to make them. I use Selmer mouthpiece, but there are many more brands like Vandoren, Yamaha...
You can take a look in this online store for more info about Clarinet mouthpieces (Brands, price and such)
The difference between closed and open mouthpiece is:
- closed mouthpiece has a smaller tip opening
- on a open mouthpiece clarinet players use less hard reeds
I started to use a closed mouthpiece when i played 3 years, because my tutor said that i would make better sound with harder reeds. I found out that on my closed mouthpiece best reed hardness is 4.5(Vandoren silver). Depends on a reed brand. I also used reeds with hardness 4.