Process and transducers submerged in a fluid for emitting low frequency acoustic waves with lightened horns

A process for emitting low frequency acoustic waves into a fluid from a transducer for transmitting waves within a frequency range using a determined input power and according to a given electro-acoustic efficiency, wherein

• a) the transducer comprises at least one horn solid with an extremity of a motor pillar, a rigid box delimiting with the at least one horn an internal cavity enclosing the motor pillar and having determined dimensions and volume,
• b) behind said at least one horn and inside said box a dynamic load solid with the box is arranged, the dynamic load closing partially an internal section of the box and dividing the internal cavity into a front cavity and a rear cavity, the front and rear cavities communicating, and
• c) a peripheral external edge of said at least one horn and an internal wall of the box are close together,
• the process comprising emitting acoustic waves using the determined input power at frequencies lower than an initial range and at a maximum output power.