Abstract: The object of the present invention is a process wherein transducers submed in a fluid for emitting low frequency acoustic waves with lightened horns are used to reduce the frequency of emission for a given maximum power consumption of the transducer. The transducer transmits waves in a frequency range according to the given maximum power consumption and a given electro-acoustic efficiency. The transducer comprises at least one horn solid with the extremity of a motor pillar and a rigid box. The rigid box encloses the motor pillar and has determined dimensions and external volume, and further includes a dynamic load solid with the rigid box. The dynamic load partially closes an inside section of the rigid box and divides an internal cavity into a front cavity and rear cavity. The front and rear cavities communicate.