vibraphones <p>Metallophones consisting of tuned, graduated metal bars arranged in two rows suspended from a metal frame with tubular resonators suspended below them; motor-driven spinning discs fixed above the open tops of the resonators produce the unique vibrato characteristic of the instrument.</p> <p>Source: Art &amp; Architecture Thesaurus</p> <p>http://vocab.getty.edu/page/aat/300041914</p>