Abstract: The present invention is a method and apparatus for simply and inexpensively enhancing an electronic audio signal in such a way that the quality of audible sound produced from the audio signal more closely approaches that of the original sound heard live in an acoustically designed environment. The present invention restores the perception of harmonics that are normally missing in an electronic audio signal. The apparatus includes a circuit that causes an input audio signal to be distorted such that an enhanced audio signal is produced that exhibits an improved harmonic quality compared to that of the original input audio signal. This distortion is a non-linear amplification of enhancing harmonics or frequencies in the input audio signal. That is, a band of desirable harmonics or frequencies in the input audio signal are non-uniformly amplified across the band. This band of frequencies from the input audio signal can be a band of high frequencies and/or a band of low frequencies.

Abstract: An electro-acoustic speaker having no permanent magnet. An audio input signal is applied to a pair of parallel coils, each being in series with a diode. The diodes are oppositely acting, so that the coils conduct during alternate half cycles of the input signal. As a result, the coils alternately generate magnetic flux for cooperative establishment of an unidirectional magnetic field. The input signal is also applied to a third coil for generation of a full wave current therethrough. This full wave current produces magnetic flux which establishes an alternating magnetic field. Interactions between the current-carrying coils and their respective magnetic fields produce acceleration forces for a speaker cone.

Abstract: Apparatus and methods for enhancing an electronic audio signal by adding enhancing harmonics to the electronic audio signal. The present invention includes a field inducing coil through which input electronic audio signals are to be transmitted to set up an electromagnetic field. The field inducing coil is weakly coupled to an electromagnetic field receptor such that when an input electronic audio signal is transmitted through the inducing coil only a small portion of the electromagnetic field cuts or passes through the field receptor in order to produce an induced electronic audio signal having a greater harmonic content than the input electronic audio signal.