One of my euphonium students is working on a Simone Mantia theme and variations piece. The first lesson, the student presented the piece and it brought back memories of practicing in Mantia’s advanced method book, The Trombone Virtuoso, with my first trombone teacher Dr. James Roberts. It is not as popular a method book now because of many publications since, but his explanation of tone-production is priceless.
Mantia states, “the best way to improve the quality of one’s tone is to practice sustained notes. This should be done regularly every morning before playing anything else.” He goes into detail about starting the tone at (pp) then a gradual crescendo to (ff) then decrescendo back down to (pp). The key is to do this over all registers of the horn, as low as you can play comfortably and equally as high. This type of practice gives total control of all registers and also a more focused sound on each note.
The sustained notes’ changing dynamics is even more profound in Charles Vernon’s method book, The Singing Trombone. On page 16, Vernon gives great examples of how a brass player should approach long tones as the dynamics change with crescendo and decrescendos. In my opinion he gives the best description of what one should listen for while playing, “all that changes during the crescendo or decrescendo should be the speed of the air.”
On that note go practice your long tones.