Pioneer Electronic Corporation

Yoshiki Ohta

Fumio Matsushita

Satoshi Kumada

Minoru Yoshida

Keishi Saito

Katsumi Amano

A rear speaker and a front speaker are provided in a room. A microphone is disposed at a listening position between the front and rear speakers for picking up a first sound from the front speakers and a second sound from the rear speaker. Time lags of the first sound and the second sound is obtained from the outputs of the microphone, and the time difference between the time lags is obtained. An antiphase audio signal opposite to a reflected composite signal included in the first sound picked up by the microphone is provided by the sound field correcting circuit. The antiphase audio signal with the same amplitude is delayed based on the time difference and emitted from the rear speaker so as to cancel the reflected composite signal.

Audio system

A speaker system for use in an automobile vehicle, comprises: a pair of front speakers for converting electric signals fed from a two-channel source into sound signals; a band pass filter for extracting a signal component having a frequency substantially satisfying .lambda.=2L when the automobile vehicle has a length L; a phase adjusting circuit for adjusting the phase of an electric signal; and a rear speaker for converting an electric signal fed through the phase adjusting circuit and the band pass filter into a sound signal.

Speaker system for use in an automobile vehicle

A speaker system for use in an automobile vehicle, comprises: pair of side speakers disposed on left and right sides in a front section within the automobile vehicle; a central speaker disposed in a middle position between the two side speakers; a pair of delay circuits connected on two signal lines leading to the side speakers disposed on the left and right sides within the vehicle; an adder connected between the left and right channels to add together the electric signals transmitted from the left and right channels so as to produce a sum signal; and a band pass filter connected on a signal line leading to the central speaker, said band pass filter being constructed and adjusted to eliminate a high frequency signal component. The sum signal fed from the adder is passed through the band pass filter before being applied to the central speaker.

Growing community of inventors

Saitama-ken, Japan

Yoshiki Ohta