Gulbransen, Inc.

Cbs Corporation

David T Starkey

Anthony G Williams

J Robert Lee

A new, inexpensive and unobtrusive opto-electronic sensor which requires no manual adjustments after installation under the keys of the piano keyboard. Post-installation manual adjustments are unnecessary because a method embodied in a computer program and performed by a microprocessor digitally adjusts the operating ranges of the keys. After electronic adjustment, the opto-electronic sensors are scanned and sampled according to another portion of the method to determine the current key position and velocity. The key position and the velocity determined by the method are then transmitted in a MIDI compatible data stream.

Opto-electronic sensing method and device for an acoustic piano

A technique for digitally processing a counterpart of a musical sound first transforms a set of time-domain samples of the sound into frequency-domain counterparts and then gradually coerces the frequency-domain counterparts into integer multiples of a fundamental frequency of the sound.

Method and apparatus for producing an electronic representation of a

A method for operating a digital synthesizer type of electronic musical instrument to rapidly make available digital oscillators to produce newly keyed notes even when all digital oscillators are currently active with previous assignments. The method contains a way of maintaining a record of the digital oscillator with the lowest amplitude, and reassigning this lowest amplitude digital oscillator to produce the new note on the rationale that the output of the lowest digital oscillator will be the least missed if an output has to be prematurely curtailed. Beside just a straight amplitude critereon, the method also allows for prioritizing some low amplitude outputs over others to make a more pleasing performance. The invention also includes an apparatus for performing the method.

Reassignment of digital oscillators according to amplitude

An electronic musical instrument of the digital synthesis type that uses digital processing techniques to impart not only the desired harmonic structure and pitch, but also to impart the correct amplitude and envelope. Only after all of the harmonic structure processing, all amplitude scaling, and all panning/mixing has been performed in digital circuitry, are the four outputs converted by digital to analog converters into analog musical outputs. Part of the digital processing includes a digital scaling circuit using a barrel interpolator to scale each sample from 1/2 to 31/32 and a shift right register to scale each sample between 1 and 1/32,768.

Method and apparatus for digitally generating musical notes

A digital synthesizer type electronic musical instrument that has the ability to automatically accompany a pre-recorded song with appropriate chords. The pre-recorded song is transposed into the key of C major, divided into a number of musical sequences, and then stored in a data structure. By analyzing the data structure of each musical sequence, the electronic musical instrument also can provide intelligent accompaniment, such as voice leading, to the notes that the operator plays on the keyboard.

Method and apparatus for intelligent chord accompaniment

A digital tone generator for a keyboard electronic musical instrument is described. The generator is of the waveshape memory type and repetitively interpolates between successive stored sample points thereby to effectively multiply the number of samples representing the waveshape so as to produce an output tone signal having reduced quantization error. Envelope errors are minimized by using cascade-connected multiplying digital-to-analog converters for multiplying the waveshapes derived from the interpolation with digital signals representative of an envelope waveshape. The system also includes a novel modification of a known multiplying digital-to-analog converter which greatly increases its speed of operation and makes possible the generation of clean output tone signals at the extremely high bit rates required to accomplish the interpolation.

Growing community of inventors

San Diego, CA, United States of America

David T Starkey