An apparatus for generating an acoustic energy pulse and delivering it into a body is described. The apparatus includes a generator for creating an acoustic energy pulse having an energy density field that can be measured at all points within a space in the shape of an imaginary cylinder having a length greater than or equal to 2 cm and a diameter. The cylindrically shaped space has a cylinder longitudinal axis oriented relative to a longitudinal axis of the energy pulse at an angle in the range from zero to twenty degrees. A minimum energy density for the pulse at all locations within the cylindrically shaped space is at least 50% of a maximum energy density for the pulse within the space.