The Vandoren V12 clarinet reeds are made using cane with the same diameter used for alto saxophone reeds. As a result, they have a thicker heel and are cut on a longer palette with a slightly thicker tip than the Traditional. These come in a box of 5 individually-wrapped reeds.
Due to this, they are usually slightly stronger than the Traditional reeds (e.g. if you normally play on a 3 1/2 strength on the Traditional cut reeds, you may want to consider a 3 strength V12 cut reed to play on).
The longer palette means that more of the reed is vibrating, resulting in a deeper, richer sound. The thicker tip gives body to the attack and also increases the longevity of the reed.
The introduction of the 3 1/2+ strength allows a smaller and more specific gradation, resulting in reeds that are more consistent within the same strength. Resulting in reeds that are more consistent within the same strength.
Have you heard of Vandoren's new VK1 Synthetic Reed? Find them here!