Victor Company of Japan, Limited

Yasuhisa Okabe

Yasuo Itoh

Shinji Nakamura

Nobuaki Takahashi

Yoshiki Iwasaki

Kazunori Nishikawa

Tomohiro Mouri

Toshiyuki Iida

Masaaki Satoh

Katsuhiro Ohba

Hideaki Ozaki

Tatsuo Sawada

Nobuhide Ohsaki

Nobuaki Suda

Yoshiaki Tanaka

In a contents sale system, original contents data are encrypted into encryption-resultant contents data in response to original playback key data. The original playback key data are encrypted into first encryption-resultant playback key data. The first encryption-resultant playback key data are encrypted into second encryption-resultant playback key data in response to an ID of a sale destination terminal apparatus. The encryption-resultant contents data and the second encryption-resultant playback key data are transmitted to the sale destination terminal apparatus. The sale destination terminal apparatus is enabled to decrypt the second encryption-resultant playback key data into the first encryption-resultant playback key data in response to the ID of the sale destination terminal apparatus. The sale destination terminal apparatus is enabled to decrypt the first encryption-resultant playback key data into the original playback key data. The sale destination terminal apparatus is enabled to decrypt the encryption-resultant contents data into the original contents data in response to the original playback key data.

Contents sale system

A surround signal processing apparatus by which an inputted rear surround signal can be reproduced, together with two-channel front stereophonic signals, through a pair of speakers arranged in front of and in substantially right-and-left symmetry about a listener, in such a way that two sound images of the reproduced rear surround signal can be localized at two predetermined positions relative to the listener. The inputted rear surround signal is processed by a filter. The signal processed by the filter is added to one of the stereophonic signals, and then outputted to one of the pair of speakers. Further, an inversion signal of the filter-processed signal is added to the other of the stereophonic signals, and then outputted to the other of the speakers. Here, the transfer characteristics of the filter are determined as follows: (F-K)/(S-A), where S denotes transfer characteristics between one of the speakers and one of the listener's ears positioned on the same side as the speaker, respectively; A denotes transfer characteristics between one of the speakers and one of the listener's ears positioned on an opposite side to the speaker, respectively; F denotes transfer characteristics between one of the two positions at which two sound images are required to be localized and one of the listener's ears positioned on the same side as the image position, respectively; K denotes transfer characteristics between one of the two positions at which the two sound images are required to be localized and one of the listener's ears positioned on an opposite side to the image position; and/denotes a reverse convolution calculation.

Surround signal processing apparatus

A surround signal processing apparatus, by which an inputted rear surround signal can be reproduced, together with two-channel front stereophonic signals, through a pair of speakers arranged in front of and in substantially right-and-left symmetry about a listener, in such a way that two sound images of the reproduced rear surround signal can be localized at two predetermined positions relative to the listener. The inputted rear surround signal is processed by a filter. The signal processed by the filter is added to one of the stereophonic signals, and then outputted to one of the pair of speakers. Further, an inversion signal of the filter-processed signal is added to the other of the stereophonic signals, and then outputted to the other of the speakers. Here, the transfer characteristics of the filter are determined as follows: (F-K)/(S-A), where S denotes transfer characteristics between one of the speakers and one of the listener's ears positioned on the same side as the speaker, respectively; A denotes transfer characteristics between one of the speakers and one of the listener's ears positioned on an opposite side to the speaker, respectively; F denotes transfer characteristics between one of the two positions at which two sound images are required to be localized and one of the listener's ears positioned on the same side as the image position, respectively; K denotes transfer characteristics between one of the two positions at which the two sound images are required to be localized and one of the listener's ears positioned on an opposite side to the image position; and / denotes a reverse convolution calculation.

Two closed loops including a base bias controlling circuit are provided in a single ended push-pull amplifier. The base bias controlling circuit controls base bias voltages of respective transistors constituting the final stage of the push-pull operation so that a predetermined small amount of collector current flows via each of the collector-emitter paths of the transistors irrespective of the presence and absence of the input signal. Because of the predetermined collector currents, none of the transistors is held at cutoff in operation, thereby preventing the occurrence of the crossover distortion.

Single ended push-pull amplifier

An angle modulated wave demodulation system demodulates an input angle modulated wave by means of a phase locked loop system which comprises a phase comparator, which is operated responsive to an input angle modulated wave. A voltage controlled oscillator is supplied with a part of the output of the phase comparator which controls its oscillation frequency. The oscillator supplies its oscillation frequency to the phase comparator. The phase locked loop system has a lock frequency range which decreases its width when the level of the input angle modulated wave is below a predetermined level. The portion of this lock range in which the width of the lock range decreases is positively utilized. The voltage controlled oscillator oscillates at a frequency equal to the center frequency of the carrier of the input angle modulated wave, when the phase locked loop becomes unlocked.

Angle modulated wave demodulation system

Growing community of inventors

Isehara, Japan

Yasuhisa Okabe