| LOOK at a mouthpiece.
Place a ruler dircetly across the center.
This is where it is widest.
If your lips are 50/50 then you have the widest possible surface area for vibrations.
Move either up or down (it doesn't matter) and the amount of vibrating surface is reduced.
The only difference in moving up vs down is in possible volume.
Since the top lip is the vibrating lip if you pin it down it can't get the amplitude to play loudly. (So when you play lower in the cup more lip CAN move and you can get louder) but as far a range goes it doesn't matter on the whole. It is merely what a given person gets used to. IT can work equally in that regard.
BTW LOOKS are extremely decieving in this regard. Many people have one lip bigger than the other. So what may LOOK like more of one lip in the cup than another; is really the 2 lips meeting in the center of the mouthpiece. (We can't see the center from pictures but only with visualizers, cut away pieces, clear pieces etc.) |