Vibrato changes following imagery.

Objectives: This study investigated acoustic change in singers' vibrato following imagery and non-imagery tasks.

Study Design: The study used a fully randomized cross-over (six conditions × two times) block design, in which each singer received each intervention in random order. Data were analyzed using the general linear model (GLM).

Singer and listener perception of vocal warm-up.

Objectives: This study investigated changes perceived by singers and listeners after the singers had vocally warmed up.

Study Design: The study used a repeated measures within-subject design to assess changes in vibrato quality from pre (nonwarmed-up voice) to post (warmed-up voice) test. Intraclass correlation coefficients were calculated to assess singers' self-ratings pre- and posttest and intra- and interlistener rater reliability.

Vocal warm-up produces acoustic change in singers' vibrato rate.

Vibrato rate and vibrato extent were acoustically assessed in 12 classically trained female singers before and after 25 minutes of vocal warm-up exercises. Vocal warm-up produced three notable changes in vibrato rate: (1) more regularity in the cyclic undulations comprising the vibrato rate of a note, (2) more stability in mean vibrato rates from one sustained note to the next, and (3) a moderating of excessively fast and excessively slow mean vibrato rates. No significant change was found for vibrato extent.