At times, in the student-resistance anthem "Coracao de Estudante," for example, he entered a falsetto, not just as an extreme register to add a little color but also as a comfortable place to stay.

These are, in turn, dissected and ornamented by the soloist with formidable virtuosity, using multiple-stopping and harmonics and, notably in the cadenza, the extreme upper register of the violin.

Laura Claycomb, the new Amanda, sings into the extreme high register that was sketched before.

These notes are far apart for most of the instrument's range, making diatonic and chromatic playing impossible except in the extreme high register.

The Allmusic review states "Throughout, Harris (whose mastery of the extreme upper register and immediately recognizable sound are both quite impressive) is in excellent form".

Ferguson was not the first trumpeter to play in the extreme upper register, but he had a unique ability to play high notes with full, rich tone, power, and musicality.

The soprano Claudia Barainsky, whose voice swings and perches with astonishing ease in the extreme high register, is outstanding among the soloists in this recording.

It is hard to convey the uncanny effect of his full, fluid, lustrous tone, poised in the extreme upper register without the slightest strain.

The violins have to play in an extreme, stratospheric register for long stretches of the 25-minute piece, and even for these supremely gifted musicians, it's a huge challenge.

Mr. Sciarrino's quartets, admirably played by the Accardo Quartet, provided a set of glimpses through a microscope, glimpses at small, teeming worlds of sound in the extreme high register.