Abstract: A device for providing a sound field by adjusting the listener's interaural correlation coefficient. A sound field adjustment filter is provided with a pair of filter circuit groups corresponding to a left and right channel. This filter divides a desired frequency band of the audio signal into multiple frequency bands and assigns prescribed transmission characteristics to generate a sound field adjustment signal for each frequency band such that a prescribed impulse response is configured cooperatively for the entire desired frequency band of the audio signal. The transmission characteristics adjust the audio signal for each split frequency band by the addition of time delay and gain. By means of operation output units, the filter adds the sound field adjustment signals generated by each of the filter circuit groups to the audio signal of the other channels, and outputs to stereo speakers.

Abstract: [Problems to be Solved] At regeneration of sounds by a speaker having common vibration boards for left and right channels allows an audience to percept a broader sound field. [Means for Solving the Problems] An acoustic regeneration system for regenerating sounds by a speaker 20 provided with a transparent panel 24 of a liquid crystal apparatus and oscillators 26 fro vibrating the transparent panel 24 in response to signals of left and right channels is provided with a pair of input terminals 32 receptive of signals of the left and right channels, a prescribed band-pass characteristics for a plurality of prescribed bands, a pair of sound field adjustment filters 38, an operational output 32 for subtracting signals of other channels past the sound field adjustment filters 38 from the input left and right channel signals to output the result as the channel signal of a corresponding signal of the speaker 20 and a delay circuit arranged before the operational output 36.

Abstract: An acoustic echo erasing apparatus which generates a pseudo-echo component from an audio reception signal (a vector x.sub.1) using an adaptive filter, and removes the pseudo-echo component from an audio transmission signal (a vector y). The apparatus extracts a feedback component depending only on the audio reception signal from the audio transmission signal, and passes the audio reception signal through the adaptive filter to generate the pseudo-echo component while setting a transfer characteristic of the adaptive filter in accordance with the feedback component.

Abstract: A plurality of speakers are arranged in line, and a plurality of digital filters are provided for the speakers. Each of the digital filters is applied with a plurality of audio signals. Characteristics of each digital filter is adjusted so as to provide patterns of directivity to each speaker dependent on the input audio signals.

Abstract: First and second processing circuits are provided for carrying out a reverberation process of an input signal, and first and second filters are provided for applying amplitude characteristics to output signals of the first and second processing circuits. A first adder is provided for adding an output signal of the first processing circuit with an output signal of the second filter at opposed phase, and a second adder is provided for adding an output signal of the first filter with an output signal of second processing circuit in-phase. First and second speakers are provided to receive output signals of the first and second adders. The first and second amplitude characteristics are determined in accordance with a correlation coefficient of sound pressures of sounds from the first and second speakers.

Abstract: A plurality of reverberation signal generating circuits are provided for generating a plurality of reverberation signals from input audio signals of two channels. Each of the reverberation signals has a predetermined function of correlation. A pair of filters are provided for controlling the function of correlation of the reverberation signal and for applying controlled reverberation signals to reverberation speakers, thereby providing a sound field.

Abstract: A rectangular nickel-metal hydride secondary cell permits improving the air-tightness and also permits preventing a metal case from being deformed in a step of folding an open end portion of the metal case. The rectangular nickel-metal hydride secondary cell, includes a rectangular cylindrical metal case having a bottom, an electrode group housed in the metal case, an alkali electrolyte contained in the metal case, a rectangular sealing plate mounted near the open end portion of the metal case. An insulating gasket is interposed in a compressed state between the inner wall near the open end of the metal case and the sealing plate. The metal case comprises a folded portion formed by inwardly folding the open end portion of the metal case and an inwardly projecting stepped portion formed along the inner surface of the metal case below the folded portion.

Abstract: A rectangular nickel-metal hydride secondary cell permits improving the air-tightness and-also permits preventing a metal case from being deformed in the step of folding an open end portion of the metal case.

Abstract: A rectangular nickel-metal hydride secondary cell permits improving the air-tightness and also permits preventing a metal case from being deformed in the step of folding an open end portion of the metal case.

Abstract: A speaker system including a common input terminal for receiving an audio signal to be acoustically radiated; several speaker units; several digital filters connected between the common input terminal and the speaker units, and a filter coefficient for each of the digital filters. The speaker units are arranged linearly, in a matrix form or in a honeycomb form.

Abstract: There is disclosed a sound field correcting apparatus for adding indirect sound signals to audio signals from a decoder when a steering emphasis operation is not executed in a decoder and for limiting the addition of the indirect sound signals when the steering emphasis operation has been performed by the decoder. Thus, a reproduction sound having a proper extent feeling and a movement feeling of a sound image is obtained in accordance with a scene of a video image.

Abstract: A stereo sound system for reproducing signals from two independent channels through right and left speakers. The two speakers are centrally located and propagate a lesser part of their acoustic output directly into free space. Two acoustic tunnels separately couple the major part of the outputs of the respective speakers and have their issuing ends far removed on either side of the speakers. The tunnels provide advantageous delay.