Abstract: A common electrode driver includes an inverting amplifier including a first resistor, a second resistor, and an operational amplifier, and a resistance ratio adjustment circuit that adjusts, in accordance with a length of one horizontal scan period, a resistance ratio being a ratio of a resistance value of the second resistor to a resistance value of the first resistor. A feedback voltage is provided to one end of the first resistor. The resistance ratio adjustment circuit sets the resistance ratio when second driving is performed, in which a length of one horizontal scan period is a second time longer than a first time, to be smaller than the resistance ratio when first driving is performed, in which a length of one horizontal scan period is the first time.

Abstract: There is provided an earphone device of an ear-hole insertion type having a noise cancelling function, the earphone device including a left channel housing unit that accommodates a left channel driver unit outputting a left channel sound; and a right channel housing unit that accommodates a right channel driver unit outputting a right channel sound. A microphone for noise cancelling and a battery are accommodated in each of the left and right channel housing units.

Abstract: There is provided an earphone device of an ear-hole insertion type having a noise cancelling function, the earphone device including a left channel housing unit that accommodates a left channel driver unit outputting a left channel sound; and a right channel housing unit that accommodates a right channel driver unit outputting a right channel sound. A microphone for noise cancelling and a battery are accommodated in each of the left and right channel housing units.

Abstract: There is provided an earphone device of an ear-hole insertion type having a noise cancelling function, the earphone device including a left channel housing unit that accommodates a left channel driver unit outputting a left channel sound; and a right channel housing unit that accommodates a right channel driver unit outputting a right channel sound. A microphone for noise cancelling and a battery are accommodated in each of the left and right channel housing units.

Abstract: A sound reproducing device includes: a plug section configured to receive input of L-channel and R-channel audio signals; an L-channel housing section including at least an L-channel driver unit configured to produce sound on the basis of the L-channel audio signal, an L-channel microphone configured to collect external sound, and an L-channel microcomputer configured to perform setting control on noise-canceling processing on the basis of a collected sound signal of the microphone; an R-channel housing section including a same corresponding configuration as those of the L-channel housing section; and an in-cord housing section formed so as to be inserted in a wiring cord for supplying the signals inputted from the plug section to the L-channel and the R-channel housing sections, wherein the in-cord housing section is provided with a communication terminal for allowing data communication between the L-channel microcomputer and the R-channel microcomputer, and an external apparatus.

Abstract: There is provided an earphone device of an ear-hole insertion type having a noise cancelling function, the earphone device including a left channel housing unit that accommodates a left channel driver unit outputting a left channel sound; and a right channel housing unit that accommodates a right channel driver unit outputting a right channel sound. A microphone for noise cancelling and a battery are accommodated in each of the left and right channel housing units.

Abstract: A sound reproducing device includes: a plug section configured to receive input of L-channel and R-channel audio signals; an L-channel housing section including at least an L-channel driver unit configured to produce sound on the basis of the L-channel audio signal, an L-channel microphone configured to collect external sound, and an L-channel microcomputer configured to perform setting control on noise-canceling processing on the basis of a collected sound signal of the microphone; an R-channel housing section including a same corresponding configuration as those of the L-channel housing section; and an in-cord housing section formed so as to be inserted in a wiring cord for supplying the signals inputted from the plug section to the L-channel and the R-channel housing sections, wherein the in-cord housing section is provided with a communication terminal for allowing data communication between the L-channel microcomputer and the R-channel microcomputer, and an external apparatus.

Abstract: A headphone section 10 having microphone elements 14L, 14R for detecting a sound around the user and signal acoustic transducing elements 15L, 15R which function as a sound source for canceling the sound around the user housed in the headphone boxes 13L, 13R and a control circuit section 20 that includes a noise canceling headphone together with the headphone section 10 are separately configured. The control circuit section 20 is adjusted in such a manner that variation can be reduced and predetermined frequency characteristics and gain characteristics are achieved at a predetermined frequency. To the headphone section 10, gain adjusting sections 16L, 16R are equipped.

Abstract: The signal source of the reference frequency of a PLL 20 is composed of a VCO 24. A VCO 14 is provided. A first audio signal (L+R) is supplied to the VCO 24 so as to control its oscillation frequency f24. A second audio signal (L−R) is supplied to the VCO 14, so that an FM signal SSUB is formed whose occupied frequency band is outside the band of the first audio signal (L+R). This FM signal SSUB is supplied to an adder 26, hereby added to a phase comparison output that is supplied to a VCO 21 from a low-pass filter, and then supplied to the VCO 21.

Abstract: An electro-acoustic transducer having a main body portion 4 housing at least a speaker unit, a pinna inserting portion 5 protruding from the main body portion and adapted for being inserted into a pinna of a user, an elastically deformable auditory canal fitting portion 12, 51 provided on the outer periphery of the pinna inserting portion and an insertion control portion 46, 52 for controlling an insertion position of the auditory canal fitting portion 12, 51 into the auditory canal. By inserting the pinna inserting portion 5 into the pinna, the auditory canal fitting portion 12, 51 is deformed to conform to the shape of the auditory canal and fitted in the auditory canal in this state for hermetically sealing the auditory canal. The insertion control portion 46, 52 is retained by a portion of the pinna for controlling the inserting position of the auditory canal fitting portion 12, 51 in the auditory canal.