Electro-acoustic transducers

In an electro-acoustic transducer formed of a loudspeaker enclosure including a side wall having a form of revolution about a longitudinal axis, each end of which is closed by a loudspeaker, the two loudspeakers being mounted back to back one above the other in vertical alignment with each other and aligned with the longitudinal axis of the enclosure, solely one of the loudspeakers being fed from an electric power source and being an "active" loudspeaker, whereas the other loudspeaker is "passive" in that said "passive" loudspeaker receives no electric supply, and movements of said passive loudspeaker solely result from a rear wave of the active loudspeaker imparted thereto by said active loudspeaker, the enclosure being maintained vertically along an axis of revolution with both speakers mounted coextensively with the opposite ends of said side wall, said side wall not extending beyond said "active" loudspeaker, the side wall of the enclosure being formed of a non-resonsating flexible material, unlikely to resonate with the front and rear waves of the loudspeakers;

• and
• a rigid disk fixed to each outermost end of said enclosure, each said disk being formed of a very absorbant acoustic material and having a diameter slightly greater than a diameter of said speakers.