Kabushiki Kaisha Kawai Gakki Seisakusho

Tetsusai Kondo

Hiroshi Matsunaga

Haruhiko Matsui

Hisamitsu Honda

Tatsuya Inaba

Masahiko Akita

Toshio Oka

An automatic performing apparatus that executes recording and reproduction of a performance includes a diagnostic signal generator for sending a power supply control circuit at least one of normal and abnormal diagnostic signals indicating whether a controller is normally executing a program. The power supply control circuit controls the power supplied to a drive circuit by interrupting the power or reducing the power to such a low level that the drive circuit is not damaged by a prolonged power supply if the operation of the controller is determined abnormal based on the diagnostic signal generated by the diagnostic signal generator.

Automatic performing apparatus with power supply controller

An automatic performing system includes a performance information transmitting unit and a performance information receiving unit. Performance information is transmitted from the performance information transmitting unit to the performance information receiving unit. The transmitting unit waits for returned performance information from the receiving unit and compares the returned information with the transmitted information. If the returned information is determined to be unequal to the transmitted information, a retransmission command is transmitted to the receiving unit, thereby prohibiting the receiving unit from using incorrectly received performance information and ordering the receiving unit to wait for the next transmission from the transmitting unit. Thus, correctly received performance information is processed on a real time basis.

Automatic performing system capable of detection and correction of

A play data recording apparatus for a keyed musical instrument converts keying strength information, which is detected by an appropriate detector when one of keys of a keyboard apparatus is operated, into reference keying strength information based on the relationship obtained in advance between keying strength information detected when one of the keys of the keyboards is operated at an arbitrary one or ones of fractionized reference sound volumes and reference keying strength information obtained by digitizing the fractionized reference sound volumes, and then causes the reference keying strength information obtained by the conversion to be stored as one of play data into a storage device.

Play data recording apparatus for keyed musical instrument

An apparatus for automatic playing of a piano has storage register for storing play information, which includes key depression force information, and that sequentially reads the play information from the storage register and that uses included key depression force to activate operation terminals. The apparatus comprises: volume designating circuitry for designating volume; a volumn control information generator for generating volume control information in agreement with a volume designated by the volume designating circuitry; a calculator for performing a specified arithmetic operation involving the key depression force information and the volume control information, which is generated by the volume control information generator, to obtain new key depression information; and a controller for driving the operation terminals based on the new key depression force information that is provided by the calculator.

Volume control apparatus for an automatic player piano

An apparatus for automatic playing of a piano, the apparatus activating operation terminals in consonance with received play data to play music. The apparatus includes an input device for receiving play data, the play data including soft pedal event information and key event information. The apparatus also includes: a soft pedal history storage unit that, when the soft pedal event information is received from the input device, temporarily holds ON/OFF history of a soft pedal in consonance with the soft pedal event information; a converter that, when the key event information is received from the input device and the soft pedal history storage unit is storing an ON event for the soft pedal, performs a predetermined conversion of key depression force data that is included in the key event information; and a controller that controls the operation terminals in consonance with the key depression force data that has been converted by the converter.

Self playing piano and an apparatus for automatic playing of a piano

A recording/reproducing method and device for an automatic performing piano which not only seizes performance information according to occurrence and timing of an on-event, but also converts the performance information according to actual emission timing in each respective recording and reproducing process steps, thereby achieving accurate performance reproduction with balance and high fidelity. Since a time lag between depression of key and emission of sound varies with the intensity in depressing of the keys, this time lag is incorporated into performance information to be stored, a key drive solenoid can be actuated or terminated in immediate response to the output of key depression or release data, respectively.

Method and device for preventing imbalance of sound emissions in an

A device and method prevents the imbalance of emission timing between strong key strokes and weak key strokes in an automatic performing piano by preventing the occurrence of reverse phenomenon and overlap phenomenon by correcting cessation timing according the order or sequence of key strokes. A reverse phenomenon, where cessation timing for one key stroke precedes its counterpart emission timing, is prevented by changing cessation timing to occur after emission timing. An overlap phenomenon, where emission timing for the latter of two successive strokes precedes cessation timing for the former stroke, is prevented by changing the cessation timing to occur prior to the emission timing. The method and device thus achieves reproduction of performance with balanced and controlled sound emission timing and high fidelity in performance reproduction.

A solenoid drive system enabling an automatic performing apparatus to control the intensity of key depression with respect to individual keys. Voltage waveform data is provided for each of the solenoids to drive an associated keys. One cycle of the voltage waveform data is divided in a predetermined time period into a predetermined number of bit segments. A value of '1' or '0', representing a pulse height level of the control signal for each respective key is written to each and every bit segment. Duty cycle of the square wave of each of the control signals can be thus precisely varied according to and to match the key depression intensity. The voltage waveform data may be written to sequential addresses in the memory, and read out from non-sequential addresses in the memory. Alternatively, the voltage waveform data may be written to non-sequential addresses in the memory and read out from sequential addresses in the memory.

Solenoid drive system for an automatic performing apparatus

A sensor arrangement for an automatic piano player apparatus is provided. The sensor arrangement includes a plurality of switches which are operatively associated with a rotatable shutter in the hammer system of the automatic piano player. When the hammer system is operated to strike a string of the piano, the cooperation between the rotatable shutter and the switches produces output information which includes the string-striking intensity information and the state of condition information of the damper that is normally in contact with the piano string. With this information, the various play techniques such as staccato, legato, continuous key-striking and the like may be reproduced with great fidelity by the automatic piano player apparatus.

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Hamamatsu, Japan

Tetsusai Kondo