  Graphene has extremely low mass density and high mechanical strength, key
qualities for efficient wide-frequency-response electrostatic audio speaker
design. Low mass ensures good high frequency response, while high strength
allows for relatively large free-standing diaphragms necessary for effective
low frequency response. Here we report on construction and testing of a
miniaturized graphene-based electrostatic audio transducer. The
speaker/earphone is straightforward in design and operation and has excellent
frequency response across the entire audio frequency range (20HZ - 20kHz), with
performance matching or surpassing commercially available audio earphones.
