 All three stressed that the mouthpiece should be placed higher on the top lip for a more free vibration of the lips.This embouchure method, advocated by a minority of brass pedagogues such as Jerome Callet, has not yet been sufficiently researched to support the claims that this system is the most effective approach for all brass performers.Advocates of Callet's approach believe that this method was recommended and taught by the great brass instructors of the early 20th Century.