Listed only by Irwin, who says: An open metal Flute of 8' or 4' manual pitch, with a bell-shaped top of from one-half to one-eighth speaking length on each medium-scale cylindrical pipe. Some additional high overtones do escape these pipes and make the tone brighter, an opposite effect from that of the conically topped Koppelflöte. This may be a solo or ensemble Flute.
No examples of Glockenflöte are known. Contributions welcome.