Chord identification system for electronic musical instruments

• US 4,389,914 A
• Filed: 06/18/1981
• Issued: 06/28/1983
• Est. Priority Date: 06/18/1981
• Status: Expired due to Fees

• Current Assignee: Gibson Piano Ventures, Inc., UOP Llc (Honeywell International Inc.)
• Original Assignee: Baldwin Piano Incorporated (Gibson Brands, Inc.)
• Inventors: Simmons, Carlton J. Jr., Uetrecht, Dale M.
• Primary Examiner(s): Witkowski, Stanley J.
• Application Number:
  US06/275,082
• Time in Patent Office: 740 Days
• Field of Search: 84/1.01, 84/1.03, 84/1.17, 84/1.24, 84/DIG. 12, 84/DIG. 22, 84/DIG. 25, 84/445
• US Class Current: 84/669
• CPC Class Codes: G10H 1/383 Chord detection and/or recognition, e.g. for correction, or automatic bass generation
• CPC Class Codes: G10H 2210/596 Chord augmented
• CPC Class Codes: G10H 2210/601 Chord diminished
• CPC Class Codes: G10H 2210/606 Chord ninth, i.e. including ninth or above, e.g. 11th or 13th
• CPC Class Codes: G10H 2210/621 Chord seventh dominant
• CPC Class Codes: G10H 2210/626 Chord sixth
• CPC Class Codes: Y10S 84/22 Chord organs

Abstract

The present invention relates to a process and apparatus for use in musical instruments. In particular, the invention is useful for identifying a chord played on a keyboard of a musical instrument, such as the accompaniment manual of an electronic organ, and for identifying the root and the type of chord being played. Pursuant to the invention, a microprocessor used in conjunction with the instrument selectively causes the associated circuitry of the pedal and/or accompaniment keyboard of the musical instrument to play automatically in an appropriate octave either the identified root or a sequence of notes which is compatible with the identified root and chord. A pedal override feature is also provided which overrides the chord identification invention when the musician plays one or more pedal notes.

Claims

1. A process for identifying the chord type and root represented by the actuation of one or more playing keys of a musical instrument keyboard capable of representing a group of chord types based on a group of roots, each of the playing keys corresponding to one note, said process employing a switch matrix and multiple-location memory and comprising the steps of:

scanning said switch matrix and comparing the state of the switches therein to the state of corresponding bits in said multiple-location memory;

selectively enabling a means for chord identification;

determining the chord type and the root of the chord being played by selectively iteratively transposing said chord whereby said chord is identifiable by the number of notes contained therein and the interval relationship thereof; and

storing in said multiple-location memory said chord type and said root for processing, whereby said processing generates a signal for the synthesis of music which is compatible with the chord being played.

3. The process according to claims 1 or 2 wherein the enablement of said chord identification means is inhibited by the presence of a signal generated by the activation of at least one pedal key of the pedal keyboard of an electronic organ.

2. A process for identifying the chord type and root represented by the actuation of one or more playing keys of a manual keyboard of a musical instrument capable of representing a group of chord types based on a group of roots, each of the playing keys corresponding to one note, said process employing a switch matrix and multiple-location memory and comprising the steps of:

selectively enabling a means for chord identification;

selectively transposing the chord through an identifiable number of semi-tones;

determining the existence of a fifth interval in the chord being played on the manual keyboard;

selectively counting the number of notes being played on the manual keyboard;

selectively identifying the note intervals in the chord being played;

deriving a chord type; and

generating a signal dependent upon the chord type, whereby said signal is available for the synthesis of music on a pedal keyboard which is compatible with the chord being played on the manual keyboard.

4. An apparatus for identifying the chord type and root note represented by the actuation of one or more playing keys of a musical instrument keyboard capable of representing a group of different chord types based on a group of different roots, each of said playing keys corresponding to one note, said apparatus employing a switch matrix and multiple-location memory and comprising:

means for iteratively scanning said playing keys and for storing a multi-bit data representation of said playing keys in said multiple-location memory means;

means for comparing the state of key switches of said switch matrix to the state of corresponding bits in said multiple-location memory and for repetitively updating the state of keyboard status flags;

means for selectively enabling a chord identification means;

means for determining the root of the chord being played by selectively iteratively transposing said chord through an identifiable number of semi-tones;

means for selectively counting the number of notes and for determining the interval relationship thereof in said chord and for identifying the chord type; and

means for storing in said multiple-location memory said identified chord type and said root for processing, whereby said processing generates a signal for the synthesis of music which is compatible with the chord being played.

5. The apparatus according to claim 4, whereby said selectively enabling means is inhibited by the presence of a signal generated by the activation of at least one pedal key of the pedal keyboard of an electronic organ.

6. The apparatus according to claim 4 or 5, whereby all of said means are controlled by at least one microprocessor.