An apparatus for generating acoustic waves, the apparatus having: a
support structure; two tines extending from the support structure so that
proximal ends of the two tines are attached to the support structure so
that distal ends of the two tines are positioned with standoffs relative
to a dimension of the support structure and the distal ends of the two
tines are uninhibited, wherein the two tines each comprise a moment arm;
and an oscillator in mechanical communication with the two tines.