Abstract: An acoustic transducer comprising a light weight diaphragm is disclosed in which the internal vibrational resonant modes of the diaphragm are prevented or blocked without damping effects by mounting of the diaphragm on a rigid base parallel thereto by means of a multiplicity of similar parallelograms with flexible corners having dynamically rigid sides the lengths of which are a small part of the wavelength therein of the highest frequency acoustic waves to be transduced with no two adjacent parallelograms being spaced from each other by a distance which is more than a small part of the wave length in the diaphragm of the highest frequency acoustic waves to be transduced. Preferred embodiments are described in which the diaphragm is divided into elements by the parallelograms with the individual elements made rigid by means other than the materials used, for example, by providing appropriate shape or tension in such element.

Abstract: A loudspeaker comprising a plurality of stages extended along a predetermined direction, each stage of which includes a movable diaphragm having a resonance out of the frequency range of reproduction and movable within a support structure. The diaphragms are driven transversely in unison by a distributed drive system capable of propagating longitudinal acoustical waves at a very high velocity and therefore also nonresonant within the range of the speaker. The drive system is connected to suitable electro-acoustic motional transformer such as a moving coil permanent magnet system. The coil longitudinal drive means and diaphragm masses are made exceedingly low so that the collective mass is comparable to the air mass in the immediate vicinity of the speaker which air mass serves to load the same. No damping materials are employed.

Abstract: A sound reproducing movable diaphragm utilizes a three hinge, double rigid member arrangement for connecting a movable diaphragm to a fixed member or baffle or adjacent movable diaphragm in order to decouple unwanted distortions and resonances from the system.

Abstract: An electro-acoustic transducer for low frequencies ranging from 0-5000 Hz uses a plurality of parallel spaced apart, alternately disposed, fixed and movable diaphragms, in addition to which the motion inducing forces on the movable diaphragm are distributed over the area of the diaphragm and assembly of the electro-acoustic transducer is achieved by the use of modular elements.