The Hang was developed in the year 2000 and introduced at the Musikmesse Frankfurt in 2001. It is 52 cm in diameter and has a height of 24 cm. The two deep drawn steel hemispheres of the Hang are hardened by a process known as gas-nitriding. The side considered the 'bottom' has an opening  in the center which allows the generation of the bass note through Helmholtz resonance. All are tuned harmonically  around a low note at the center of the tone circle. 

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