Yamaha Corporation

Tsutomu Sasaki

Yuji Fujiwara

Shigeru Muramatsu

Tomoyuki Ura

Tadaharu Kato

Jun Yamamoto

Kiyoshi Kawamura

Yasuhiko Oba

Tomoya Sasaki

Yasuhiko Ohba

Shigeki Iida

Masahisa Hashimoto

A mute piano is responsive to key movements and pedal movements so as to produce music data codes expressing the pitch of tones and pedal effect to be given to the tones in accordance with the MIDI protocols, and the damper pedal stroke is divided into a rest region, a half-pedal region and a damper-free region which are expressed by difference numerical ranges of data bytes of the musical data code: since the piano has its own individuality, the relation between the pedal position and the value of data bytes is to be calibrated; the controller of the mute piano enters a calibration mode, and optimizes the relation to the actual damper actions, thereby causing the music data code exactly to express the effect of the damper pedal to be given to the tones.

Musical instrument having controller exactly discriminating half-pedal and controlling system used therein

An automatic player piano is equipped with an electronic supporting system, which makes a player learn an optimum pedal stroke to a half pedal region; while the player is practicing a music tune on the piano, the electronic supporting system monitors the damper pedal; when the player starts to depress the damper pedal, the electronic supporting system exerts an assisting force on the damper pedal so as to make the player feel the damper pedal light; when the damper pedal reaches an entrance of the half pedal region, the electronic supporting system removes the assisting force from the damper pedal so that the player feels the damper pedal heavy, whereby the player learns the pedal stroke to the half pedal region through the change of load borne by the player.

Electronic supporting system for musicians and musical instrument equipped with the same

A keyboard musical instrument provides plural keys of a keyboard to be driven by an automatic playing system; although the automatic playing system selectively drives the keys in accordance with a performance rule expressing a music tune, a motion controller of the automatic playing system changes the performance rule if the human player drives the keys different from those defined in the performance rule so that the automatic playing system changes a part of the music tune in real time fashion during the automatic performance.

Keyboard musical instrument

While a player is fingering a music tune on a piano, an electronic assistant system monitors the keys to see whether or not the player starts to produce tones through a particular playing technique such as repetition; when the electronic assistant system finds particular key movements unique to the particular playing technique in an early stage, the electronic assistant system decides that the player intends to produce the tone through the particular playing technique, and forces the key to travel on a reference key trajectory in the later stage, whereby the player learns the particular playing technique.

Electronic assistant system for lesson in music and musical instrument equipped with the same

An electronic proof system is provided in association with an automatic player piano; while a human player is practicing a music tune on the acoustic piano, the electronic proof system monitors the pedals of piano to see whether or not the player brings the pedals to target pedal positions; if the current pedal position is spaced from the target pedal position, the electronic proof system gives rise to fine vibrations of the pedal, and makes the player notice the pedal staying at incorrect pedal position through the tactile impression.

Electronic proof system and musical instrument equipped with the same

An automatic player musical instrument is a combination of an acoustic piano and an electric system, which serves as an automatic playing system and an electronic proof system, and a controller of the electric system has an information processing capability; when a user instructs the electric system to check performance on the keyboard, a subroutine program for electronic proof starts to run; while the user is fingering a music tune, the controller monitors the keys with key sensors to see whether or not the user correctly plays the music tune; when the user mistakenly depresses a key instead of another key, the controller gives rise to vibrations of the mistakenly de-pressed key so as to give a notice of incorrect fingering to the user.

Musical instrument with electronic proof system, electric system and computer program

In an automatic player piano, hammer sensors monitor associated hammers so as to report current positions on the hammer trajectories, and a data processor analyzes the hammer motion for producing pieces of music data representative of the performance on the acoustic piano; the aged deterioration is influential in the relative position between the hammers and the hammer sensors so that the data processor rectifies the relative position, the data processor determines the turning point at which the hammer changes the direction of motion, and compares the current value indicating the turning point with the previous value; if the difference is found, the data processor adds a value of deflection of strings to the current value so as to determine and memorizes the true value of the turning point; the data processor analyzes the hammer motion on the basis of the true value so that the music data are reliable.

Musical instrument, music data producer incorporated therein and method for exactly discriminating hammer motion

A key sensor-less automatic player piano includes, key actuators so as to give rise to key motion without any fingering of a human player, key sensors producing key position signals expressing key motion and a data processing unit producing music data codes during a performance on the keyboard and a playback table expressing a relation between the hammer velocity and a reference key velocity; while the data processing unit is recording the performance, the hammer velocity is estimated on the basis of a key velocity-to-hammer velocity conversion table already prepared through an experiment where the keys are depressed by a human player; while the data processing unit is preparing the playback table, the hammer velocity is estimated on the basis of another velocity conversion table prepared through another experiment where the keys are actuated by the key actuators.

Automatic player musical instrument with velocity conversion tables selectively accessed and electronic system used therein

An electronic system, which serves as a recorder and an automatic player, is installed in an automatic player piano, and hammer sensors, which are implemented by photo couplers, report current hammer positions through analog signals to a data processor so that the data processor analyzes pieces of hammer data for recording the performance in a set of music codes; the analog signals are amplified through an operational amplifier and, thereafter, converted to discrete values of digital hammer signals so that an offset voltage is unavoidably introduced into the analog signals; when the photo couplers vary the light-to-photocurrent converting characteristics due to the aged deterioration, the data processor takes the offset voltage into account, and calibrates the hammer sensors, thereby making the digital hammer signals correctly express the current hammer positions.

Transducer free from aged deterioration, musical instrument using the same and method used therein

Detector detects movement of a hammer (driven member) that strikes a string (abutted member) by moving in response to operation of a key. On the basis of detection outputs of the detector and a given abutment-presuming reference value, it is presumed that the hammer has struck or abutted against the string. For example, performance event data is generated on the basis of the abutment presumption. In order to minimize errors due to variation over time or aging of a hammer action mechanism, a determination section determines that the hammer has, actually or with a high probability, reached an abutting position where the hammer abuts against the string, and the abutment-presuming condition in accordance with the determination result. It is determined that the hammer has reached the abutting position, by comparing, on the basis of detection outputs of the detector, movement of the hammer toward the string and movement of the hammer away from the string. By thus making a string-striking determination in view of operation of the hammer not only before the string striking but also after the string striking, it is possible to accurately determine whether or not the string has been struck.

Keyboard musical instrument and other-type musical instrument, and method for generating tone-generation instructing information

An automatic player piano is a combination between an acoustic piano and an electronic system serving as a recorder and an automatic player; while a user is fingering a piece of music on the acoustic piano, the player strongly depresses some keys and softly depresses other keys so as to give artistic expression to the tones, and the depressed keys give rise to hammer motion at different values of hammer velocity; since the hammer velocity is proportional to the loudness of tones, the controller is expected exactly to determine the hammer velocity; the hammers travel on linear trajectories and parabolic trajectories depending upon the hammer velocity so that the controller estimates the hammer velocity by using different methods, whereby the controller can produce music data codes exactly expressing the tones to be produced.

Velocity estimator for manipulators and musical instrument using the same

An automatic player piano is only equipped with key sensors, and the automatic player is expected to give rise to hammer motion to be varied together with the loudness of tones; the manufacturer prepared not only a velocity conversion table expressing a relation between measured values of the hammer velocity and measured values of the reference key velocity but also a reference table expressing a relation between measured values of hammer velocity and target values of reference key velocity through experiments, and the velocity conversion table and reference table were stored in a suitable memory in the automatic player; the automatic player determines a playback table partially through an experiment and partially through transcription from reference table so as to drive the hammers without influence of unstable key motion at large loudness.

Automatic player musical instrument having playback table partially prepared through transcription from reference table and computer program used therein

Keys, which are incorporated in an automatic player piano, are monitored with an optical transducer system. The optical transducer system includes sensor heads provided on both sides of the key trajectories, LEDs connected to predetermined sensor heads through optical fibers, LDDs connected to the other sensor heads through optical fibers and a controlling unit. A luminescence controller is connected to the LEDs for optimizing the luminescence, and bias controllers are respectively connected to the LDDs. The luminescence controller and bias controllers optimize the luminescence of emitted light and the bias level of electric signals so that the optical transducer system is free from the individuality of component parts and the deterioration.

Optical transducer system having light emitting elements and light detecting elements both regulable in output characteristics

A light emitting device includes an optical fiber plug formed with a through-hole into which a bundle of optical fibers is inserted and a light-emitting device holder formed with a through-hole in which a condenser lens and a light emitting device are accommodated, and the optical fiber plug is assembled with the light-emitting device holder so that the light emitting device is optically coupled to the optical fiber through the condenser lens; a positioning device, a hyperboloid lens surface or a reflecting surface is formed in the optical fiber plug/light emitting device holder, condenser lens or the inner surface of the light-emitting device holder so that the light incident on the light input end is increased by virtue of the exact positioning between the optical fiber and optical axis, reduction of aberration or increase of light directed to the condenser lens.

Light emitting unit operative at high coupling efficiency, optical sensor system and musical instrument using the same

A hammer sensor includes a photo-filter plate movable together with a hammer assembly and having a base plate fixed to the hammer shank and an arc pattern formed on the base plate and different in transparency from the base plate, a photo radiating element radiating a light beam toward the arc pattern and a photo detecting element disposed on the optical path of the light beam for converting the amount of transmitted light to an electric signal, wherein the photo-filter plate converts the rotational angle of the hammer assembly to the amount of light incident on the photo detecting element, and makes the photo radiating element and the photo detecting element stationary so that a suitable photo-shield case prevents the photo elements from environmental light.

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Hamamatsu, Japan

Tsutomu Sasaki