Re: High C tone quality problem
I would be surprised - theres a mechanism that will only bend in, preventing the upper octave mech from opening far enough. It would be a REALLY freak thing if it got bent out, like a watch band catching in it, and you pull extremely hard without untangling, or a snagged shirt, which I think would most likely rip before it bent it. But then it is a yanagisawa, the brass standards might be softer than most other saxes.
I am not sure what you mean by wa-wa, but I suspect you mean it has a "wolfy" tone. (not sure if that is how you spell "wolfy" or not.) Thats caused from your auxilary F key being bent in too much, closing the 2 pads slightly. You probably have the problem in both octaves, but dont notice it in the lower.