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Masayuki Iwamatsu, Hamamatsu-Shi JP

Masayuki Iwamatsu, Hamamatsu-Shi JP

Patent application numberDescriptionPublished
20080297257Amplifier - The amplifier comprises an inverting negative feedback amplifier circuit using an operational amplifier, a comparator for comparing the potential of the negative phase input terminal of the operational amplifier with the reference potential Vref of the comparator, and a low-pass filter. The imaginary short state of the operational amplifier is lost when clipping occurs on the output signal. It is thus possible to detect clipping by monitoring the potential of the negative phase input terminal.12-04-2008
20090052696Electroacoustic transducer - An electroacoustic transducer includes a single package, a microphone provided in the single package, an amplifier provided in the single package, and a controller provided in the single package. The microphone converts an acoustic pressure into an electrical signal. The amplifier amplifies the electrical signal that is output from the microphone. The amplifier is configured to allow the gain to be adjustable. The controller controls the gain of the amplifier, with reference to the level of an output signal from the amplifier, so as to prevent the output signal from being clipped.02-26-2009
20090091355Amplifier - An amplifier includes: an operation amplifier including a positive input terminal and a negative input terminal; and a detector which detects that a difference between a voltage of the positive input terminal and a voltage of the negative input terminal is equal to or exceeds a predetermined value and outputs a detection signal.04-09-2009
20090141911ACOUSTIC PROCESSING DEVICE AND ACOUSTIC PROCESSING METHOD - An acoustic processing device, includes an inputting section which receives a first audio signal and a second audio signal, a first input signal amplifying section which amplifies the first audio signal at an amplification factor, a second input signal amplifying section which amplifies the second audio signal at an amplification factor, a first initial delayed amplifying section, a first adding section which adds the first audio signal amplified by the first amplifying portion and the first audio signal amplified by the first input signal amplifying section, a second adding section which adds the first audio signal amplified by the second amplifying portion and the second audio signal amplified by the second input signal amplifying section, a first supplying section which supplies an audio signal output from the first adding section to a first sound emitting section, and a second supplying section which supplies an audio signal output from the second adding section to a second sound emitting section different from the first sound emitting section.06-04-2009
20090147134AUDIO SIGNAL SUPPLYING DEVICE, PARAMETER PROVIDING SYSTEM, TELEVISION SET, AV SYSTEM, SPEAKER APPARATUS, AND AUDIO SIGNAL SUPPLYING METHOD - An audio signal supplying device includes a connection terminal which is connected to a speaker unit and which outputs an audio signal to the speaker unit, a specifying section which specifies a type of the speaker unit connected to the connection terminal, an acquiring section which acquires a parameter corresponding to the type of the speaker unit specified by the specifying section from an outside, a storing section which stores the parameter acquired by the acquiring section, an inputting section into which the audio signal is input, an acoustic characteristic controlling section which adjusts an acoustic characteristic of the audio signal input into the inputting section based on the parameter stored in the storing section, and a supplying section which supplies the audio signal whose acoustic characteristic is adjusted by the acoustic characteristic controlling section to the connection terminal.06-11-2009
20100127778Amplifier - An amplifier includes: a variable gain unit that adjusts an amplitude of an input signal and outputs a first signal; an amplitude limiting unit that limits an amplitude of the first signal and outputs a second signal set to have an amplitude of a first amplitude value or less; an amplifying unit that amplifies the second signal to output the amplified second signal as an output signal; and a control unit that detects when the first signal has an amplitude of a second amplitude value or more to control a gain of the variable gain unit so that the amplitude of the first signal becomes less than the second amplitude value, the second amplitude value being larger than the first amplitude value.05-27-2010
20110026735Noise reducing circuit - A noise reducing circuit includes a variable low-cut filter disposed at an upstream of a sound signal switching section and has a variable cutoff frequency, and a control circuit which controls the cutoff frequency of the variable low-cut filter to a first cutoff frequency lower than a cutoff frequency of a low-cut filter disposed at downstream of the variable low-cut filter when a switching instruction is not issued from a switching instructing section, and increases the cutoff frequency of the variable low-cut filter to a second cutoff frequency higher than the first cutoff frequency when the switching instruction is issued. The switching of the sound signal switching section is executed after a predetermined period elapses since the switching instruction is issued, and the control section decreases the cutoff frequency of the variable low-cut filter to the first cutoff frequency after the switching of the sound signal switching section is completed.02-03-2011
20110068872Amplifying apparatus - An amplifying apparatus amplifies an input signal supplied to an input terminal and outputs an output signal from an output terminal. The apparatus includes a high-potential power supply line through which a high voltage is supplied; a low-potential power supply line through which a low voltage is supplied; a control unit; and a power supply in which one of the high and low voltages is a fixed voltage, and which generates, as the other of the high and low voltages, one of a first voltage in which a polarity of the fixed voltage is inverted, and a second voltage which is closer to the ground potential than the first voltage is. The control unit controls the power supply to cause the other of the high and low voltages to be switched between the first voltage and the second voltage in accordance with a signal level of the output signal.03-24-2011

Patent applications by Masayuki Iwamatsu, Hamamatsu-Shi JP