Conventional loudspeaker membranes made of metal or synthetic material such as fabric, ceramics
or plastics suffer from nonlinearities and cone breakup modes at fairly low audio frequencies. Due
to their mass, inertia and limited mechanical stability the speaker membranes made of conventional
materials cannot follow the high frequency excitation of the actuating voice-coil. Low sound
velocity causes phase shift and sound pressure losses due to interference of adjacent parts of the
membrane at audible frequencies.