Electronic piano circuit
US3935783A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1974 |
| Grant date | Feb 3, 1976 |
| Priority date | — |
| Expiry date | Jul 8, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10H1/057
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
The embodiment of the invention disclosed herein is directed to an electronic musical instrument of the keyboard type used to electronically reproduce piano sounds. The circuit has means to vary the amplitude of the piano voice in response to the velocity of the downward movement of the key. Means are provided for producing a fundamental square wave frequency and the second and fourth harmonics thereof, in response to the actuation of a given key on the keyboard. One circuit arrangement includes means for combining the fundamental frequency and the second and fourth harmonics in a predetermined time relation to produce the zero, attack, peak, and decay characteristics of a piano voice as actually produced by a piano string. Amplitude limiting means are coupled to the circuit for controlling the amplitude of the harmonics in response to predetermined values so that mixing of the fundamental frequency and the second and fourth harmonics along predetermined points of the piano voice characteristics curve will more accurately reproduce electronically the sounds of a piano. Another circuit arrangement provides means for rapid recovery of the piano circuit so that the keys can be actuate…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.