| The high soprano range was investigated by acoustic and electroglottographic measurements of twelve sopranos and high-speed endoscopy of one soprano. A single laryngeal transition was observed on glides above the primo passaggio. It supports the existence of two distinct laryngeal mechanisms in the high soprano range: M2 and M3, synonymous with head and whistle laryngeal registers. The laryngeal transition occurred gradually over several tones within the D#5-D6 interval. It was completed at a higher pitch and over a wider range by trained than untrained sopranos. The upper limit of the laryngeal transition on glides was accompanied by pitch jumps or instabilities but, for most singers, it did not coincide with the upper limit of R1:f0 tuning (i.e. tuning the first-resonance to the fundamental frequency). However, pitch jumps were also associated with changes in resonance tuning. Four singers demonstrated an overlap range over which they could sing with a 'full head' or 'fluty resonant' quality. Glottal behaviors underlying these two qualities were similar to the M2 and M3 mechanisms respectively. Pitch jumps, discontinuous glottal and spectral changes characteristic of a M2-M3 laryngeal transition were observed on decrescendi produced in this overlap range. |