The HANG: A hand played steel drum
Thomas D. Rossing, Uwe J. Hansen, Felix Rohner, Sabina Schärer · The Journal of the Acoustical Society of America · 2001
The HANG is a new steel instrument consisting of two spherical shells of steel, suitable for playing with the hands. Seven to nine notes are harmonically tuned around a central deep note which is formed by the Helmholtz resonance. Elliptical note areas are formed on the upper shell and tuned so that the (1,1)a and (1,1)b modes of each note area have frequencies that are in the ratios of 3:2:1 with respect to the fundamental, except in the highest notes where they are in the ratio of 2.5:2:1 or 2.4:2:1. Holographic studies show the modal shapes and also the extent of coupling between note areas.