Pioneer Electronic Corporation

Nippon Telegraph and Telephone Corporation

Yasuo Gan

Hideaki Morikawa

Takashi Oyaba

Naobumi Kanemaki

Koushiro Kogure

Takashi Ooyaba

A horn shaped baffle is provided in the front of a loudspeaker. Escape holes are formed in the horn shaped baffle so as to emit sound waves deviated from the axis of the loudspeaker. A sound absorptive panel is provided on the outside of the baffle so as to cover the holes.

Loudspeaker

A speaker system comprises an acoustic panel. The acoustic panel is constructed of a plurality of thin plate-like sound absorbing panels provided close to the loudspeaker and arranged such that major surfaces thereof are disposed with a predetermined space therebetween so that the front space of the loudspeaker is opened for guiding a sound wave forwardly to radiate along the surface of the panels, while components of the sound wave having a radiation direction oblique to the major central axis of the sound absorbing panels are attenuated due to propagation through the sound absorbing panels. The sound absorbing panels are made of a porous sound absorbing material in which metal powders of Al, Ni, Cu, and others are sintered. In the case where one side of the acoustic panel is opened, it is preferable to provide a sound absorbing material at least at that opening and to further enclose the periphery of the sound absorbing material with a sound insulating material.

Speaker system having directivity

A speaker system comprises a pair of speakers for a higher frequency range and a pair of speakers for a lower frequency range. The speakers for the lower range are disposed with a space d.sub.1 equal to the wavelength .lambda..sub.c of a division frequency f.sub.c of a reproduction frequency range, and speakers for the higher range are disposed with a space d.sub.2 =d.sub.1 /4 to d.sub.1 /2 in the middle of the lower frequency speakers. Another speaker system comprises a speaker for reproducing signals in a lower frequency range of a reproduction frequency range to be reproduced, and a speaker for reproducing a higher frequency range of the frequency range, wherein a sound path dividing construction is provided for dividing the sound path of each of the speakers into two paths to provide openings for the lower frequency range and the higher frequency range. The openings for the lower frequency range are disposed with a space d.sub.1 therebetween while the openings for the higher frequency range are disposed with a space d.sub.2 therebetween, where d.sub.1 =.lambda..sub.c .+-.50% and d.sub. 2 =d.sub.1 /4 to d.sub.1 /2.

Growing community of inventors

Saitama, Japan

Yasuo Gan