US3516321A - Electronic piano - Google Patents
Electronic piano Download PDFInfo
- Publication number
- US3516321A US3516321A US610423A US3516321DA US3516321A US 3516321 A US3516321 A US 3516321A US 610423 A US610423 A US 610423A US 3516321D A US3516321D A US 3516321DA US 3516321 A US3516321 A US 3516321A
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- capacitor
- decay
- voltage
- key
- circuit
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- 239000003990 capacitor Substances 0.000 description 86
- 238000013016 damping Methods 0.000 description 12
- 230000009471 action Effects 0.000 description 7
- 230000015556 catabolic process Effects 0.000 description 7
- 230000004048 modification Effects 0.000 description 7
- 238000012986 modification Methods 0.000 description 7
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- 238000005070 sampling Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 230000002441 reversible effect Effects 0.000 description 6
- 230000000994 depressogenic effect Effects 0.000 description 3
- 238000007599 discharging Methods 0.000 description 3
- 210000000056 organ Anatomy 0.000 description 3
- 238000013459 approach Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 229910052754 neon Inorganic materials 0.000 description 2
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 description 2
- 238000009527 percussion Methods 0.000 description 2
- 230000002829 reductive effect Effects 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000000881 depressing effect Effects 0.000 description 1
- 230000004069 differentiation Effects 0.000 description 1
- 210000000031 electric organ Anatomy 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 102220037530 rs9827878 Human genes 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10H—ELECTROPHONIC MUSICAL INSTRUMENTS; INSTRUMENTS IN WHICH THE TONES ARE GENERATED BY ELECTROMECHANICAL MEANS OR ELECTRONIC GENERATORS, OR IN WHICH THE TONES ARE SYNTHESISED FROM A DATA STORE
- G10H1/00—Details of electrophonic musical instruments
- G10H1/02—Means for controlling the tone frequencies, e.g. attack or decay; Means for producing special musical effects, e.g. vibratos or glissandos
- G10H1/04—Means for controlling the tone frequencies, e.g. attack or decay; Means for producing special musical effects, e.g. vibratos or glissandos by additional modulation
- G10H1/053—Means for controlling the tone frequencies, e.g. attack or decay; Means for producing special musical effects, e.g. vibratos or glissandos by additional modulation during execution only
- G10H1/057—Means for controlling the tone frequencies, e.g. attack or decay; Means for producing special musical effects, e.g. vibratos or glissandos by additional modulation during execution only by envelope-forming circuits
Definitions
- Devices for effecting damping on release of the key, and to disable damping in response to a pedal operation, and to provide double rate decay of voltage of the control or timing capacitor and of the sustain circuit voltage.
- the fact that the decay time of sustain voltage is slow and that decay of control voltage is rapid enables the diode or transistor toperform its isolating function.
- This invention relates generally to electronic pianos and more particularly to electrical tone generating systems having facility for producing touch sensitive tones, which decay slowly while a key is held depressed, which decay rapidly when a struck key is released, and which can be caused to decay slowly by actuating of a damping pedal when the key is released.
- a simple switch composed of two spaced stationary contacts and one movable contact which moves from one to the other stationary contact on key actuation, in conjunction with a transfer valve, enables a voltage proportional to key velocity to be developed across a control capacitor and to be instantaneously transferred to a sustain capacitor in a tone gating circuit, without affecting the decay times of the capacitors at times subsequent to the transfer.
- two parallel RC circuits are provided, one of which is a key depression timing or control circuit, and the other of which is a slow decay sustain circuit for a tone generator, such as an oscillator and gate.
- the timing or control circuit is connected to the movable arm of a single pole double throw switch, and the movable arm is normally connected to a stationary contact held to a relatively large voltage, so
- the movable arm arrives at the second contact, which is connected via a diode to the sustain circuit.
- Charge is now transferred from the capacitor of the timing circuit to the capacitor of the sustain circuit, 'via the diode.
- the timing circuit continues to decay rapidly, so that the diode becomes biased off as soon as it has transfered charge to the sustain capacitor, the latter being in a slow decay circuit.
- the sustain circuit then controls amplitude of a tone solely in accordance with its own decay characteristic, regardless of whether or not the key is maintained depressed. On release of the key the timing circuit re-attains its normal voltage substantially instantaneously.
- the timing circuit is provided with a double rate of decay.
- the usual striking of a key may occupy from 5 ms. to 30 ms. in normal piano playing. Decay of voltage of the timing capacitor is permitted down to a preset minimum value, in 30 ms., but thereafter rate of decay is sharply reduced, so that total decay may require additional 250 ms.
- This provides a base value, so that some charge will be interchanged with the sustain capacitor regardless of how light the touch is.
- the actual touch of a piano is more nearly simulated than is feasible with a single decay circuit, or than is feasible with an electromagnetic touch sensitive transducer, as in Markowitz. Decay time is then nearly hyperbolic, i.e. as l/t, instead of wholly exponential.
- decay of the sustain capacitor has a double rate, initially rapid and terminally slow, to simulate the actual decay characteristic of piano strings.
- FIG. 1 is a circuit diagram illustrated in simplified form of a basic feature of the invention, i.e. touch controlled switching and change transfer from a control to a sustain capacitor;
- FIGS. 2 and 3 are circuit diagrams of modifications of the system of FIG. 1 providing for double rate decay of voltage across the control capacitor of FIG. 1;
- FIG. 4 is a circuit diagram of a touch sensitive tone generating system employing features of FIG. 2;
- FIG. 5 is a circuit diagram of a modification of the system of FIG. 4, including damping and percussion facilities;
- FIG. 6 is a circuit diagram of a modification of the ssytem of FIG. 5, employing transistor transfer in place of diode transfer, and having novel damping facility;
- FIG. 7 is a modification of the system of FIG. 6.
- FIGS. 8 and 9 are circuit diagrams of modifications of the systems of FIG. 7, having provisions for double rate decay of tone signal.
- FIG. 1 illustrates the basic approach of the invention.
- R1C1 is a timing circuit, connected between ground (at lead 10) and a negative voltage source V.
- One terminal of each of R1 and C1 is connected directly to lead 10 and the other terminal of each of R1 and C1 is connected to a 3 switch arm A, operable upward by the key 12 of a keyboard musical instrument.
- Switch arm A is normally in contact with switch contact B, which is in turn connected to source V.
- the voltage V therefore normally exists across C1.
- switch arm A On depressing key 12 contact between switch arm A and switch contact B is broken.
- the charge on capacitor C1 now commences to decay, in accordance with the values of RlCl, and these may be arranged to provide a drop from 50 v. to v., for example, in an elapsed time of 30 ms., which may be the time required to depress a piano key with a soft impact.
- the switch arm A at the termination of key depression, makes with switch contact C, to which is connected, in cascade, the cathode of a diode and a timing circuit R2C2.
- the time constant of R202 is far greater than that of R1C1 so that once the transfer of charge is effective, and this occurs practically instantaneously, C2 is isolated from C1, because the cathode of diode 15 immediately becomes more positive than its anode.
- the timing circuit may be designed to fall to a low level in 30 ms. Values provided are exemplary of a typical action.
- timing capacitor In order to produce a dynamic range similar to that of a piano it is necessary to allow the timing capacitor to discharge rapidly at first, i.e. out to 30 ms., and after the low level has been reached to decay much more slowly for about 2.50 ms. longer.
- FIGS. 2 and 3 of the accompanying drawings Two methods are employed, illustrated in FIGS. 2 and 3 of the accompanying drawings, and these may be briefly described as:
- capacitor C1 is normally maintained charged to the sum of V1 and B2, while contacts A and B make.
- Terminal 20 is connected via a diode D1 to the large capacitor C3, the cathode of diode D1 being biased from voltage divider VD to a point between 0 v. on lead 22 and V2 on lead 23.
- VD voltage divider
- a point is reached at which the diode D1 becomes conductive, whereupon C3 proceeds to charge, increasing the time constant to R1C1C3, and decreasing the rate of charging of C1, to follow the curve 24.
- the transition point 25 may be set at about -5 v., with V2 at about 50 v.
- diode D2 is reversed, i.e. its cathode is connected to point 20, and its anode is connected to a small negative voltage V3 via a small resistance R3.
- the circuit can be analyzed by considering that current through R1 and R3 are of the same algebraic signs, so that net charging of C1 is fast via R1 and R3 in parallel, until diode D2 cuts off, i.e. point 20 becomes less nega- 4 tive than V3. After this point, 25, C1 charges only via R1, and therefore the rate is smaller, as at 24.
- FIG. 4 of the accompanying drawings A practical circuit, including circuit values, capable of providing touch sensitive piano tones in a Baldwin Model 54 electric organ is provided in FIG. 4 of the accompanying drawings. The part of the figure to the left of line L has been heretofore explained in conjunction with FIG. 2 and therefore is not further explained. Circuit values are marked B and W, for black and white keys, respectively.
- FIG. 5 utilizes essentially the timing circuit of FIG. 3, which is not again explained.
- a neon cell N is provided, in shunt to diode D3.
- One terminal of N is connected through a resistance R4 to a switch point 35.
- a movable switch arm 36 serves to connect point 35 either to a v. terminal 37 or to a +11 v. terminal 38.
- the junction of R2 and C2 is also connected to an 11 v. lead via a diode D4, which prevents degradation of low level response by providing a clamp.
- the arm 36 is moved to the 80 v. terminal when damping is desired, and to the 11 v. terminal otherwise.
- Two supplementary switches S1 and S2 are provided, which switch operation of the system to produce selectively piano tone and organ type percussive tone. With S2 closed S1 is open, and vice versa. With S2 closed v. is applied to contact C1 as in FIG. 3.
- diode D5 When switch S2 is open and S1 closed, diode D5 provides a path to a 50 v. bus from an 11 v. bus via resistance R1. C1 is then charged normally to 50 v. This voltage is transferred to contact B when key K is actuated and is maintained so lOng as the key K is actuated. On release of the key K, action is similar to that for the piano mode. The percussion mode of operation is thus not touch sensitive, but starts all notes at the same level. Either a fast or slow decay may then be provided, according as switch S3 is in the one or the other of its operative conditions.
- a timing capacitor C5 is normally maintained shorted by contacts B, A of a key controlled switch.
- Movable arm A of the switch is connected via a very large resistance R5 to a -12 v. bus 51, and via a diode D6 and a small resistance R6 to a -9 v. bus 51a.
- R6 may be 100K and R5 may be 100M, so that double rate decay occurs as in the system of FIG. 3.
- the latter includes a collector, connected directly to v. bus 50, and an emitter, connected via a small resistance R6a to a capacitor C6, in series, to -12 v. bus 51.
- Transistor T1 has its base normally connected via a large resistance R7 to the bus 51, via contacts 55, for undamped operation.
- Transistor T1 is normally biased off, by the -12 v. applied to its base, but on completion of movement of key K a momentary voltage is applied between base and collector equal to that of the capacitor C5. Thereby a charge is applied to capacitor C6.
- the diode current of the base to emitter of T1 is now supplemented by collector-emitter current.
- the transistor T1 thus momentarily conducts just as arm A makes contact with point B, and then cuts off because its emitter is then biased positively with respect to its base.
- the charge on C6 decays via R8 and via the base to emitter circuit of transistor T2, thereby varying the conductivity of T2.
- Transistor T2 is connected in series with transistor T3 which acts as a gate, having its base directly connected to bus 50 and its emitter connected to a tone signal input terminal 53, which supplies tone by a series coupling capacitor C7 and resistance R8. Tone is taken off the collector of T3. Resistance R6a prevents DC thump during sampling, smoothing the charge of capacitor C6. Diode D8 assures that no negative charge can be assumed by capacitor C6, with respect to bus 51.
- contacts 56 are caused to close, so that on release of the key K, i.e. on separation of contacts A, C, 30' v. is applied to the base of T1 via R7. This is sufficient voltage to cause the base to emitter circuit of T1 to operate in its Zener region, discharging C6 through R7 down to -12 v., i.e. with a fast decay. So long as contacts A, C, make contact the base of T1 is caught by D7, at -12 v., preventing Zener breakdown.
- the Zener breakdown characteristic of the base emitter diode of T1 when reverse biased, simulates the action of N in FIG. 5.
- the base of T1 With the damper switch connected to -30 v., and .A, C in contact, the base of T1 is maintained at -12 v. This does not provide Zener breakdown.
- a breaks from C i.e. when the key is released, the base of T1 falls towards -30 v., forcing the transistor into its Zener mode and effectively shunting R8 with R7 and increasing the discharge rate of C6.
- the damper switch in the undamped position the reverse potential on the base emitter diode of T1 never approaches the Zener breakdown voltage, and when contact A breaks from contact C, C6 continues to discharge through R8 alone.
- a diode D7 has its cathode connected to point 59 and its anode selectively to v. terminal 60 and to -12 v. terminal 61, selected by manually operated switch arm 62. With switch arm 62 up percussive action is attained, since point 59 cannot exceed 5 v., and for any normal key actuation 'will attain this value. Therefore in the percussive mode, appropriate to organ playing, 5 v. is applied to the base of T1 for each key actuation. For the piano mode point 59 cannot exceed -12 v., the same voltage as that of bus 51.
- FIG. 7 A modification of the system of FIG. 6 which has economic and operational advantages is illustrated in FIG. 7.
- the circuit of FIG. 7 does not utilize transistor gates or amplifiers, for producing tones, but instead the voltage appearing across a storage capacitor is applied to a diode gate, conventional per se.
- a tone source terminal T is provided at an input to gate 65, which proceeds via a capacitor 66 to series diodes 67, 68, identically poled, and thence to a load L.
- a parallel RC shunt extends from the junction of diodes 67, 68 to ground.
- the impedance of shunt 70 is such that when the diodes 67 68 are rendered conductive by bias voltage applied to the anode of diode 67, a relatively high shunt is presented, in comparison with series impedance, and tone signal is not unduly attenuated.
- the shunt impedance is low compared to the series impedance present, and feed through is radically reduced by being bypassed to ground.
- the tone generator type applied to terminal T must be square wave shaped. Differentiation takes place at the circuits of diodes 67, 68, to present a signal containing essentially even harmonics. These are required to produce realistic piano tones. While the gate is non-conductive, a negative ofi-bias is produced in capacitor 66 to maintain the gate non-conductive in absence of positive on-gating voltage from capacitor C6a.
- the system of FIG. 7 employs a single rate of decay.
- true piano tone decay exhibits two definite decay rates, the initial rate being greater than the terminal rate.
- the double rate decay expedient of FIG. 2 is applied to piano tone production in FIG. 8, i.e. discharge of sustain capacitor C6a occurs initially via small resistance R10 of about 39K, and large resistance R9 of 220K, until diode 10 cuts OE and thereafter only via R9.
- This system is level independent, i.e. the level at which the rate of decay decreases is independent of initial amplitude but is established by bias +2 on the diode D10.
- two capacitors C20 and C21 are employed in parallel, as sustain capacitors.
- R22 may have a value of 220K.
- R21 may have a value of K.
- the terminal rate of decay is controlled by C20 and C21 in parallel discharging through R22.
- the initial charging pulse cannot charge C21 instantaneously, because of the presence of R21. Therefore, the initial condition is that C21 is initially uncharged or slightly charged, but C20 is fully charged. Discharge of C20 then occurs initially in part into C21 and in part through R22, and hence is rapid. Ultimately C21 becomes charged, and thereafter C20 and C21 discharge together through R22.
- the oscillator and gate of FIG. 7, taken together, may be considered a tone source or generator.
- a generator may be substituted a tone oscillator, or the gate G may be a photoelectric gate, the tone source being a light modulator.
- said last means including means for reverse biasing said diode into its Zener region.
- said key being movable by impact from a first to a second position, comprising means initiating a double rate decaying voltage wave at the instant of initial impact of said key,
- said double rate decay simulating the decay of string piano tone.
- a condenser charge and discharge circuit including a single pole double throw switch, including a first contact movable between second and third stationary contacts,
- key operated means for moving said first contact between said second and third stationary contacts.
- means including a unidirectional electronic valve for only momentarily sampling the voltage of said capacitor during said discharge only at the instant of completion of a precisely predetermined movement of said key and for storing the voltage then momentarily sampled despite continuation of said discharge of said' control capacitor,
- said last means including a storage capacitor for storing said momentarily sampled voltage
- valve means includes a transistor arranged to transfer current to said storage capacitor in response to the voltage across said control capacitor.
- means including a unidirectional electronic valve for only momentarily sampling the voltage of said capacitor during said discharge only at the instant of completion of a precisely predetermined movement of said key and for storing the voltage then momentarily sampled despite continuation of said discharge of said control capacitor,
- said last means including a storage capacitor for storing said momentarily sampled voltage
- slope of the decay curve of the voltage across said storage capacitor is smaller than slope of the decay curve of the control capacitor
- said resistive discharge circuit includes means for imposing a double rate decay on the discharge of said control capacitor, said double rate decay including a relatively rapid rate of decay for approximately thirty milliseconds and a relatively slow rate of decay thereafter for about two hundred milliseconds.
- means including a unidirectional electronic valve for only momentarily sampling the voltage of said capacitor during said discharge only at the instant of completion of a precisely predetermined movement of said key for storing the voltage then momentarily sampled despite continuation of said discharge of said control capacitor,
- said last means including a storage capacitor for storing said momentarily sampled voltage
- slope of the decay curve of the voltage across said storage capacitor is smaller than slope of the decay curve of the control capacitor
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Description
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US61042367A | 1967-01-19 | 1967-01-19 |
Publications (1)
Publication Number | Publication Date |
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US3516321A true US3516321A (en) | 1970-06-23 |
Family
ID=24444955
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US610423A Expired - Lifetime US3516321A (en) | 1967-01-19 | 1967-01-19 | Electronic piano |
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US (1) | US3516321A (en) |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3617605A (en) * | 1970-03-25 | 1971-11-02 | Conn Ltd C G | Percussion keyer circuit |
US3633197A (en) * | 1968-04-26 | 1972-01-04 | Greenwood Mills Inc | Loom operation indicator circuit |
US3633198A (en) * | 1968-04-26 | 1972-01-04 | Greenwood Mills Inc | Loom operation indicator circuit |
US3666875A (en) * | 1969-07-11 | 1972-05-30 | Mario Ranzato | Electronically operated stringed instruments |
US3927594A (en) * | 1973-10-26 | 1975-12-23 | Roland Corp | Piano action |
US3999457A (en) * | 1972-03-17 | 1976-12-28 | Adolf Michel | Key system for controlling the rate of attack in electronic musical instruments |
US4033220A (en) * | 1974-06-12 | 1977-07-05 | Nihon Hammond Kabushiki Kaisha | Tempo setting device |
US4083286A (en) * | 1976-04-12 | 1978-04-11 | Faulkner Alfred H | Electronic organ keying systems |
US4095502A (en) * | 1976-05-21 | 1978-06-20 | Rhythm Band, Inc. | Sound control system in an electronic musical instrument |
US4099439A (en) * | 1974-06-14 | 1978-07-11 | Norlin Music, Inc. | Electronic musical instrument with dynamically responsive keyboard |
US4129056A (en) * | 1976-12-21 | 1978-12-12 | Jensen Richard W | Pedal control circuits for electronic piano |
US4211141A (en) * | 1978-03-17 | 1980-07-08 | Jensen Richard W | Pedal control circuits for electronic piano |
US4248123A (en) * | 1979-04-25 | 1981-02-03 | Baldwin Piano & Organ Company | Electronic piano |
US5422431A (en) * | 1992-02-27 | 1995-06-06 | Yamaha Corporation | Electronic musical tone synthesizing apparatus generating tones with variable decay rates |
US5572107A (en) * | 1993-08-27 | 1996-11-05 | Siemens Aktiengesellschaft | Switched capacitor network |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2482548A (en) * | 1942-07-15 | 1949-09-20 | Hartford Nat Bank & Trust Co | Electric piano |
US3248470A (en) * | 1963-04-24 | 1966-04-26 | Allen Organ Co | Electronic piano having means responsive to the velocity of the action |
US3306969A (en) * | 1964-03-23 | 1967-02-28 | Magnavox Co | Percussion tone generating device |
-
1967
- 1967-01-19 US US610423A patent/US3516321A/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2482548A (en) * | 1942-07-15 | 1949-09-20 | Hartford Nat Bank & Trust Co | Electric piano |
US3248470A (en) * | 1963-04-24 | 1966-04-26 | Allen Organ Co | Electronic piano having means responsive to the velocity of the action |
US3306969A (en) * | 1964-03-23 | 1967-02-28 | Magnavox Co | Percussion tone generating device |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3633197A (en) * | 1968-04-26 | 1972-01-04 | Greenwood Mills Inc | Loom operation indicator circuit |
US3633198A (en) * | 1968-04-26 | 1972-01-04 | Greenwood Mills Inc | Loom operation indicator circuit |
US3666875A (en) * | 1969-07-11 | 1972-05-30 | Mario Ranzato | Electronically operated stringed instruments |
US3617605A (en) * | 1970-03-25 | 1971-11-02 | Conn Ltd C G | Percussion keyer circuit |
US3999457A (en) * | 1972-03-17 | 1976-12-28 | Adolf Michel | Key system for controlling the rate of attack in electronic musical instruments |
US3927594A (en) * | 1973-10-26 | 1975-12-23 | Roland Corp | Piano action |
US4033220A (en) * | 1974-06-12 | 1977-07-05 | Nihon Hammond Kabushiki Kaisha | Tempo setting device |
US4099439A (en) * | 1974-06-14 | 1978-07-11 | Norlin Music, Inc. | Electronic musical instrument with dynamically responsive keyboard |
US4083286A (en) * | 1976-04-12 | 1978-04-11 | Faulkner Alfred H | Electronic organ keying systems |
US4095502A (en) * | 1976-05-21 | 1978-06-20 | Rhythm Band, Inc. | Sound control system in an electronic musical instrument |
US4129056A (en) * | 1976-12-21 | 1978-12-12 | Jensen Richard W | Pedal control circuits for electronic piano |
US4211141A (en) * | 1978-03-17 | 1980-07-08 | Jensen Richard W | Pedal control circuits for electronic piano |
US4248123A (en) * | 1979-04-25 | 1981-02-03 | Baldwin Piano & Organ Company | Electronic piano |
US5422431A (en) * | 1992-02-27 | 1995-06-06 | Yamaha Corporation | Electronic musical tone synthesizing apparatus generating tones with variable decay rates |
US5572107A (en) * | 1993-08-27 | 1996-11-05 | Siemens Aktiengesellschaft | Switched capacitor network |
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Legal Events
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AS | Assignment |
Owner name: SECURITY PACIFIC BUSINESS CREDIT INC., 10089 WILLO Free format text: SECURITY INTEREST;ASSIGNOR:BPO ACQUISITION CORP. A CORP OF DE;REEL/FRAME:004298/0001 Effective date: 19840615 Owner name: GENERAL ELECTRIC CREDIT CORPORATION, A NY CORP., C Free format text: SECURITY INTEREST;ASSIGNOR:BPO ACQUISITION CORP., A DE CORP;REEL/FRAME:004297/0802 Effective date: 19840615 |
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AS | Assignment |
Owner name: BPO ACQUISITION CORP., 180 GILBERT AVE., CINCINNAT Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:D.H. BALDWIN COMPANY AN OH CORP.;REEL/FRAME:004385/0934 Effective date: 19840615 |
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AS | Assignment |
Owner name: BALDWIN PIANO & ORGAN COMPANY Free format text: CHANGE OF NAME;ASSIGNOR:BPO ACQUISTION CORP.;REEL/FRAME:004473/0501 Effective date: 19840612 |