  Acoustic waves generated by a point source in stratified plasma are
considered in this paper. Analytical parametric solution for monochromatic
source is derived for plane-parallel polytrope model of the solar interior. The
solution is used to gain insight into the properties of the generated wavefront
as a function of excitation frequency and depth. A slowly varying pressure
perturbation moving in upper layers of solar photosphere with supersonic speed
is also considered. It is shown to excite acoustic waves putting certain
restrictions upon their geometry of the generated wavefront. The results are
discussed in relation to flare generated sunquakes.
