A clarinet expert can give a better answer, but in my case, I would get squeaks when trying to play loud because my reed was too soft, or, my mouthpiece was too closed. In either case, the reed would basically "close off" under the higher pressure of trying to play louder resulting in squeaks or no vibration at all. I've read discussions here and elsewhere that say on a clarinet, a larger tip opening does not automatically mean louder (like it usually does for a sax) but in my case it helped "open things up" and I can play louder with the more open piece.
It could also simply be a poorly-placed reed or ligature.
I know it's more prudent to look at the player first, not the equipment, but if this guy really has been playing a while, maybe it's time to consider different equipment.
It could also simply be a poorly-placed reed or ligature.
I know it's more prudent to look at the player first, not the equipment, but if this guy really has been playing a while, maybe it's time to consider different equipment.