US3722352A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pitch measurement circuit
Assignee: Individual
•
Filing: 1971-08-16
•
Granted: 1973-03-27
•
Expires: 1991-08-16
Abstract
Abstract The pitch measurement circuit, in conjunction with a two-track tape recorder and a printed instruction manual, provides a method whereby proficiency in pitch accuracy can be developed. The method is self-instructional in that the student performs into a microphone either vocally or by means of a single-tone musical instrument. The human teacher is absent, and speaks only through the manual and the tape. The student reads the music of the training items from the manual, and performs it against a setting sounded by the tape. Track 1 is an accompaniment to the student''s performance. Track 2, which the student does not hear, contains the melody in coded form, each coded tone being 40 cycles less than the corresponding tone of the melody. The student''s performance is sent from a microphone into a mixer circuit which also receives the coded melody from Track 2. The resulting mixture is demodulated, and the low-frequency component is sent to a group of frequency discriminators which by means of lights indicate whether the student is sharp, flat, or on pitch.
Inventors
- 👤 E Ihrke
- 👤 W Ihrke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:01
CPC Classifications
G; G10; G10G; G10G7/00; G10G7/02
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
96 words
A pitch measurement circuit comprising: A. means for generating a reference signal which includes a sequence of electrical signals of different frequency which correspond to a sequence of pitches to be produced by a musician; B. a microphone for picking up a sequence of sounds produced by said musician and translating the sounds into an equivalent sequence of electrical signals; C. means for comparing the electrical output signals of said microphone with said reference signal; and D. means for instantaneously indicating the relative frequency of the output of said microphone with respect to said reference signal.
Claim 2
Dependent Claim
96 words
A pitch measurement circuit comprising: A. means for generating a reference signal which includes a sequence of electrical signals of different frequency which correspond to a sequence of pitches to be produced by a musician; B. a microphone for picking up a sequence of sounds produced by said musician and translating the sounds into an equivalent sequence of electrical signals; C. means for comparing the electrical output signals of said microphone with said reference signal; and D. means for instantaneously indicating the relative frequency of the output of said microphone with respect to said reference signal.
Claim 3
Dependent Claim
106 words
A pitch measurement circuit comprising: A. means for generating a reference signal which is consistently a fixed frequency below the frequency of a note to be produced by a musician; B. a microphone for picking up sounds produced by said musician and translating the sounds into equivalent electrical signals; C. means for comparing the output of said microphone with said reference signal; and D. means electrically connected with said comparing means for instantaneously indicating the relative frequency of the output of said microphone with respect to said reference signal to indicate whether the musician''s note is sharp or whether it is flat and which it is.
Claim 4
Dependent Claim
106 words
A pitch measurement circuit comprising: A. means for generating a reference signal which is consistently a fixed frequency below the frequency of a note to be produced by a musician; B. a microphone for picking up sounds produced by said musician and translating the sounds into equivalent electrical signals; C. means for comparing the output of said microphone with said reference signal; and D. means electrically connected with said comparing means for instantaneously indicating the relative frequency of the output of said microphone with respect to said reference signal to indicate whether the musician''s note is sharp or whether it is flat and which it is.
Claim 5
Dependent Claim
46 words
A pitch measurement circuit as defined in claim 2 including adjustment means connected with said instantaneous indicating means for indicating the amount of difference between the frequency of the reference signal and the frequency of the output note which is required to actuate the indicating means.
Claim 6
Dependent Claim
118 words
A pitch measurement circuit comprising: A. means for recording a reference signals on one track of a tape recorder which indicates a sequence of pitches to be produced by a musician; B. means for recording an instrumental accompaniment for said sequence of pitches on another track of said tape recorder; C. means for simultaneously playing the reference signal and the instrumental accompaniment on said tape recorder; D. a microphone for picking up sounds of said musician and translating the sounds into equivalent electrical output signals; E. means for comparing the output of said microphone with said reference signal; and F. means for indicating the relative frequency of the output of said microphone with respect to said reference signal.
Claim 7
Dependent Claim
118 words
A pitch measurement circuit comprising: A. means for recording a reference signals on one track of a tape recorder which indicates a sequence of pitches to be produced by a musician; B. means for recording an instrumental accompaniment for said sequence of pitches on another track of said tape recorder; C. means for simultaneously playing the reference signal and the instrumental accompaniment on said tape recorder; D. a microphone for picking up sounds of said musician and translating the sounds into equivalent electrical output signals; E. means for comparing the output of said microphone with said reference signal; and F. means for indicating the relative frequency of the output of said microphone with respect to said reference signal.
Claim 8
Dependent Claim
191 words
A pitch measurement circuit comprising: A. means for generating a reference signal which is of a predetermined frequency with respect to a note to be produced by a musician; B. a microphone for picking up a sound produced by said musician and translating the sound into an equivalent electrical signal; C. means for comparing the electrical output signal of said microphone with said reference signal; D. means for indicating the relative frequency of the output of said microphone with respect to said refErence signal, E. said means for comparing the output of said microphone to said reference signal comprising a frequency mixer circuit; F. means for applying said reference signal and the output of said microphone to said mixer circuit; and G. a demodulator circuit coupled to the output of said mixer circuit, H. said means for indicating the relative frequency of the output of said microphone comprising a plurality of frequency discriminator circuits coupled in parallel to the output of said demodulator circuit, and said means also including separate indicators, one operable to indicate whether the musician is sharp and the other operable to indicate whether the musician is flat.
Claim 9
Dependent Claim
191 words
A pitch measurement circuit comprising: A. means for generating a reference signal which is of a predetermined frequency with respect to a note to be produced by a musician; B. a microphone for picking up a sound produced by said musician and translating the sound into an equivalent electrical signal; C. means for comparing the electrical output signal of said microphone with said reference signal; D. means for indicating the relative frequency of the output of said microphone with respect to said refErence signal, E. said means for comparing the output of said microphone to said reference signal comprising a frequency mixer circuit; F. means for applying said reference signal and the output of said microphone to said mixer circuit; and G. a demodulator circuit coupled to the output of said mixer circuit, H. said means for indicating the relative frequency of the output of said microphone comprising a plurality of frequency discriminator circuits coupled in parallel to the output of said demodulator circuit, and said means also including separate indicators, one operable to indicate whether the musician is sharp and the other operable to indicate whether the musician is flat.
Claim 10
Dependent Claim
66 words
A pitch measurement circuit as defined in claim 5 wherein said frequency discriminator circuits each comprise an integrating capacitor coupled to the output of said demodulator, means for periodically shorting the charge on said integrating capacitor to discharge it, and a threshold circuit coupled to said integrating capacitor and operable to produce an output indication when the charge on said integrating capacitor exceeds a predetermined level.
Claim 11
Dependent Claim
59 words
A pitch measurement circuit as defined in claim 6 wherein said means for periodically shorting the charge on said integrating capacitor to discharge it comprises a frequency divider and electronic switch means coupled between the output of said frequency divider and said capacitor for periodically discharging the capacitor at a frequency determined by the frequency of said frequency divider.
Claim 12
Dependent Claim
60 words
A pitch measurement circuit as defined in claim 7 wherein said means for producing an output indication comprises a unijunction transistor coupled to said integrating capacitor, a silicon-controlled rectifier coupled to said unijunction transistor, and an electric indicator coupled to said silicon-controlled rectifier, said indicator being operable to indicate when the charge on said integrating capacitor exceeds a predetermined level.
References Cited (Backward Citations)
US2207450A
Cited
US2919620A
Cited
US3144802A
Cited
US3163077A
Cited
US3180199A
Cited
US3598889A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |