I've tried different systems, but the one I like the best is the Claude Gordon system. I augment this with other books (like Mark Van Cleave's Max Practice, Clyde Hunt's "Sail the 7 C's", Eddie Lewis' "Daily Routines", etc..)
> 1) How much practice time each day was devoted to the course?
Hmm, 1/2 hour to an hour at least...
> 2) How much did the course increase your range?
Uhh, about a Perfect fifth... But more than increasing range, it stabilized what I already had. I don't look at the Gordon method as a "range" method per se, but rather a method to teach you to play the trumpet more efficiently.
> 3) Did the approach have any adverse affect on other aspects of your playing?
No, but it can. You must balance your practice. If you are practicing a lot of extended arpeggios, balance that with softer playing as well...
> 4) Do you continue to perform the exercises from the course?
> 5) Do you still have the added range you achieved during the course?
Of course, if not, why do it?
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