The extreme ranges of any instrument express extreme emotion, but they’re not easy to tackle. The high register is notoriously difficult on most instruments and the low register is often under-developed and under-utilized.
The standard approach towards these registers is to extend your scales and arpeggio exercises as high and as low as you can. Yes, this is a great start, and there’s no reason you shouldn’t do that, however, if you think by simply playing scales and arpeggios in these registers that you’re going to suddenly be using them creatively while you improvise, you better guess again.
And furthermore, the idea of “extending your range” does not simply mean you can play one note really high. That’s useless.How interesting is it really to hear some trumpet player squeaking out the highest note he can in the most un-musical and look-at-me manner?
Get over it. Nobody cares how high you can play. Well, not true; the same crowd that loves Kenny G, probably would love to hear you play high too. But seriously…the high and low registers can be used musically and with purpose.
Once you learn the fingerings and proper relaxed technique to achieve the sound you desire in these registers, there are some obvious but rarely used tactics to explore, which will help you become fluid in using the extreme ranges while improvising.