US4455911A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic musical instrument of frequency modulation tone synthesis type
Assignee: Yamaha Corp
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Filing: 1982-05-17
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Granted: 1984-06-26
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Expires: 2002-05-17
Abstract
Abstract An electronic musical instrument using FM tone synthesis technology produces a musical tone signal e(t) expressed as e(t)=A·sin[ωct+I·sin ωmt], where A I, ωct and ωmt represent an amplitude information, a modulation index information, a carrier frequency information and a modulation frequency information, respectively. The carrier frequency information ωct and the modulation frequency information ωmt are related to a pitch of a depressed key of the electronic musical instrument. A modulation ratio controller is further provided in the instrument. The modulation ratio controller varies the modulation ratio ωc:ωm of the carrier frequency information ωct to the modulation frequency information ωmt in accordance with the pitch of the depressed key. Such a musical tone having different harmonic constructions according to the tone pitches as that of a pipe organ is implemented by this variation of the modulation ratio.
Inventors
- 👤 Shigeru Yamada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:48
CPC Classifications
G; G10; G10H; G10H7/00; G10H7/02; G10H7/06; G10H1/00; G10H1/02; G10H1/04; G10H1/053
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
117 words
An electronic musical instrument for synthesizing a musical tone signal e(t) expressed as: e(t)=A sin [ωct+I sin ωmt] where A represents an amplitude information, I represents a modulation index information, and ωct and ωmt represent a carrier frequency information and a modulation frequency information which are related to a note pitch of a depressed key of the electronic musical instrument comprising: keyboard means having a plurality of keys; a modulation radio control information generator for generating a modulation ratio information whose value varies in accordance with a pitch of the depressed key among said plurality keys; and means for varying at least one of said informations ωct and ωmt in accordance with said modulation ratio control information.
Claim 2
Dependent Claim
117 words
An electronic musical instrument for synthesizing a musical tone signal e(t) expressed as: e(t)=A sin [ωct+I sin ωmt] where A represents an amplitude information, I represents a modulation index information, and ωct and ωmt represent a carrier frequency information and a modulation frequency information which are related to a note pitch of a depressed key of the electronic musical instrument comprising: keyboard means having a plurality of keys; a modulation radio control information generator for generating a modulation ratio information whose value varies in accordance with a pitch of the depressed key among said plurality keys; and means for varying at least one of said informations ωct and ωmt in accordance with said modulation ratio control information.
Claim 3
Dependent Claim
40 words
An electronic musical instrument according to claim 1 which further comprises a tone color setting means for setting one of a plurality of predetermined tone colors, and wherein said modulation ratio control information differs for each of said tone colors.
Claim 4
Dependent Claim
32 words
An electronic musical instrument according to claim 1 wherein said amplitude information A and said modulation index information I are respectively related to a tone color information and a depressed key information.
Claim 5
Dependent Claim
46 words
An electronic musical instrument according to claim 1 wherein said modulation ratio control information generator comprises at least two memory devices, each of which stores a modulation ratio control information determined by an octave range in which a depressed key belongs and a set tone color.
Claim 6
Dependent Claim
145 words
An electronic musical instrument comprising: keyboard means having a plurality of keys; detecting means for detecting a depressed key among said plurality of keys and outputting a key information representing a pitch of said depressed key; tone signal generating means for generating a musical tone signal e(t) expressed as e(t)=A·sin (ωct+I·sin ωmt) in response to said key information where A, I, ωct and ωmt represent an amplitude information, a modulation index information, a carrier frequency information and a modulation frequency information, respectively; modulation ratio varying means for supplying modulation ratio information corresponding to said key information to said tone signal generating means and varying the modulation ratio defined by the ratio ωc: ωm of said carrier frequency information ωct to said modulation frequency information ωmt, whereby said musical tone signal has different harmonic construction in accordance with a pitch of the tone to be produced.
Claim 7
Dependent Claim
145 words
An electronic musical instrument comprising: keyboard means having a plurality of keys; detecting means for detecting a depressed key among said plurality of keys and outputting a key information representing a pitch of said depressed key; tone signal generating means for generating a musical tone signal e(t) expressed as e(t)=A·sin (ωct+I·sin ωmt) in response to said key information where A, I, ωct and ωmt represent an amplitude information, a modulation index information, a carrier frequency information and a modulation frequency information, respectively; modulation ratio varying means for supplying modulation ratio information corresponding to said key information to said tone signal generating means and varying the modulation ratio defined by the ratio ωc: ωm of said carrier frequency information ωct to said modulation frequency information ωmt, whereby said musical tone signal has different harmonic construction in accordance with a pitch of the tone to be produced.
Claim 8
Dependent Claim
37 words
An electronic musical instrument according to claim 5 which further comprises: tone color setting means for setting one of a plurality of predetermined tone colors and wherein said modulation ratio information corresponds to said set tone color.
Claim 9
Dependent Claim
24 words
An electronic musical instrument according to claim 5 wherein said amplitude information A and said modulation index information I correspond to said key information.
Claim 10
Dependent Claim
41 words
An electronic musical instrument according to claim 5 wherein said modulation varying means varies said carrier frequency information in accordance with said modulation ratio information, whereby said modulation ratio varies in accordance with the pitch of a tone to be produced.
Claim 11
Dependent Claim
45 words
An electronic musical instrument according to claim 5 wherein said modulation varying means varies said modulation frequency information in accordance with the pitch of a tone to be produced, whereby said modulation ratio varies in accordance with the pitch of a tone to be produced.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-06-26 | 1987-12-26 | 1988-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-26 | 1991-12-26 | 1992-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-26 | 1995-12-26 | 1996-06-26 | $7700.00 | Window Closed / Lapsed |