Abstract: Provided is a digital acoustic system comprising: a ?? modulator that modulates a digital input signal and outputs a digital signal; a post-filter that is connected to the ?? modulator and which performs mismatch shaping to convert the digital signal; a parallel-serial converter that converts the digital signal converted by the post-filter into a digital signal which is serially transmitted; a serial-parallel converter that restores the digital signal converted by the parallel-serial converter; and a drive circuit which receives the digital signal restored by the serial-parallel converter, and drives drive elements to convert the signal into an analog audio signal.

Abstract: Provided is a selection device including an acquisition section for acquiring digital selection signals, and an output section for outputting selection signals to respective unit cells, each unit cell capable of being commanded to output the value zero. The selection device is characterized in that: each selection signal is for commanding the unit cell to output a value corresponding to that selection signal; the sum of the values to be output as commanded by the respective selection signals, which are output to the respective unit cells, is a value determined in association with the digital selection signal; and if the output corresponding to the digital selection signal is the value zero, then selection signals each commanding to output a non-zero value (N) are output to some of the unit cells.

Abstract: A digital sound system suitable for a digital speaker device to directly convert analog sound by a circuit using a ?? modulator and a mismatch shaping filter circuit to output a plurality of digital signals and a plurality of speakers driven by the plurality of digital signals. A digital speaker driving device includes a ?? modulator, a post filter, s driving circuits, and a power supply circuit to supply power to the ?? modulator, the post filter and the s driving elements, and the s driving circuits are adapted to s digital signal terminals.

Abstract: As one embodiment a drive circuit is disclosed. When a three-value signal including a value representing zero is input, the drive circuit outputs two two-value signals that drive two drive elements such that the difference between values representing the two two-value signals corresponds to a value representing the input three-value signal. When the value of the input three-value signal represents zero, output signals are determined in accordance with the input history of the three-value signal. The drive circuit may also be provided with a memory that records a flag value that is reversed in accordance with the input history of the input three-value signal, and the combination of the output two two-value signals being determined in accordance with the flag.

Abstract: A speaker control device in one embodiment includes a time to digital converter connected to a drive power source in series with a drive circuit for driving a plurality of coils of a speaker, the converter outputting a digital data in accordance with a voltage of the drive power source, and a monitor circuit detecting a state of the plurality of coils of the speaker based on digital data output by the time to digital converter.

Abstract: An acoustic playback system including a digital filter; and a plurality of digital modulators each of which output a digital signal to one of a plurality of speakers driven by digital signals having different play back bandwidths; wherein the digital filter converts a digital audio signal which is input into a plurality of digital audio signals of a plurality of frequency bandwidths corresponding to play back bandwidths of the speakers, and outputs each of the digital audio signals of the plurality of frequency bandwidths to one of the plurality of digital modulators; each of the digital modulators outputs the modulated digital signal to the speaker of a play back bandwidth corresponding to a frequency bandwidth of the digital audio signal which is input by performing miss-match shaping after noise shaping to a digital audio signal; and each number of bits of a digital signal of the digital modulators is different.

Abstract: An acoustic playback system including a digital filter; and a plurality of digital modulators each of which output a digital signal to one of a plurality of speakers driven by digital signals having different play back bandwidths; wherein the digital filter converts a digital audio signal which is input into a plurality of digital audio signals of a plurality of frequency bandwidths corresponding to play back bandwidths of the speakers, and outputs each of the digital audio signals of the plurality of frequency bandwidths to one of the plurality of digital modulators; each of the digital modulators outputs the modulated digital signal to the speaker of a play back bandwidth corresponding to a frequency bandwidth of the digital audio signal which is input by performing miss-match shaping after noise shaping to a digital audio signal; and each number of bits of a digital signal of the digital modulators is different.

Abstract: The disclosed conversion device converts an analog input signal into a digital signal and outputs thereof, wherein the conversion device comprises a feedback signal generator for performing mismatch shaping on the digital signal that has been converted and output, and then performing digital-analog conversion to generate a feedback signal; a subtractor for subtracting the feedback signal from the analog input signal and outputting thereof; a serial-parallel converter for converting the signal output from the subtractor into a plurality of parallel signals and outputting thereof; a vector filter for performing signal processing on the plurality of parallel signals output by the serial-parallel converter and outputting a plurality of signals; a quantizer for quantizing the plurality of signals output by the vector filter and outputting digital signals; and a parallel-serial converter for converting the digital signals output by the quantizer into serial signals and outputting thereof.

Abstract: Provided is a digital acoustic system comprising: a ?? modulator that modulates a digital input signal and outputs a digital signal; a post-filter that is connected to the ?? modulator and which performs mismatch shaping to convert the digital signal; a parallel-serial converter that converts the digital signal converted by the post-filter into a digital signal which is serially transmitted; a serial-parallel converter that restores the digital signal converted by the parallel-serial converter; and a drive circuit which receives the digital signal restored by the serial-parallel converter, and drives drive elements to convert the signal into an analog audio signal.

Abstract: As one embodiment of the present invention, provided is a drive circuit to which a three-value signal including a value representing zero is input, and that outputs two two-value signals that drive two drive elements such that the difference between values representing the two two-value signals corresponds to a value representing the input three-value signal, the drive circuit being characterized by the combination of the output two two-value signals when the value of the input three-value signal represents zero being determined in accordance with the input history of the three-value signal. The drive circuit may also be provided with a memory that records a flag value that is reversed in accordance with the input history of the input three-value signal, and the combination of the output two two-value signals being determined in accordance with the flag.

Abstract: A digital/analog conversion apparatus for converting a digital signal into an analog signal. The digital/analog conversion apparatus can generate a high-quality analog signal, even when elements configuring the digital/analog conversion apparatus have variance, with high resolution and a small circuit size. The data conversion apparatus is provided with a first data converter for reducing the number of bits of an input signal, a second data converter for converting the format of the first output signal, and a third data converter for conversion into a code which corresponds to the history of the output from the second data converter.

Abstract: A digital sound system suitable for a digital speaker device to directly convert analog sound by a circuit using a ?? modulator and a mismatch shaping filter circuit to output a plurality of digital signals and a plurality of speakers driven by the plurality of digital signals. A digital speaker driving device includes a ?? modulator, a post filter, s driving circuits, and a power supply circuit to supply power to the ?? modulator, the post filter and the s driving elements, and the s driving circuits are adapted to s digital signal terminals.

Abstract: A digital sound system suitable for a digital speaker device for directly converting analog sound by a circuit using a ?? modulator and a mismatch shaping filter circuit to output a plurality of digital signals and a plurality of speakers driven by the plurality of digital signals. A digital speaker driving device includes a ?? modulator, a post filter, s driving circuits, and a power supply circuit to supply power to the ?? modulator, the post filter and the s driving elements and the s driving circuits are adapted to s digital signal terminals.

Abstract: A digital/analog conversion apparatus for converting a digital signal into an analog signal. The digital/analog conversion apparatus can generate a high-quality analog signal, even when elements configuring the digital/analog conversion apparatus have variance, with high resolution and a small circuit size. The data conversion apparatus is provided with a first data converter for reducing the number of bits of an input signal, a second data converter for converting the format of the first output signal, and a third data converter for conversion into a code which corresponds to the history of the output from the second data converter.