I worked on Deprovenza for more than a year but could only hit the G#
once. My voice gave out after the first verse. I began study with a teacher in Palo Alto. I believe she was a student with Stenberg. We vocalized with humming only! At first I thought I was wasting my money, but one day after my lesson I returned to my studio and the aria was on the radio and I was overjoyed when I went through the first verse effortlessly, but went on to the second verse without any effort at all! You just do the regular 5-9 scale, think behind the mask and hum the excersise. It really did work for me. Another teacher had me doe excersises in falsetto, and I was very impressed with the improvement through these exercised also.