Choroi Copper Glockenspiels. This glockenspiel has removable, pure copper tone bars that form a slightly curved playing surface. The copper creates a warm, bell-like tone with a relatively short sustain. Thus the metallophonic interference, or the tonal friction between two intervals, is low. Copper Diatonic Glockenspiel - 10 tones, A=440 Hz. Wood, 35x21x20 cm (13.8x8.27x8.87 inch), A= 440 Hz, 10 copper plates, with mallet, range: c''-d''-e''-f''-g''-a''-b''-c'''-d'''-e'''.