US3839592A

US3839592A - Plural mode automatic bass system with pedal sustain

Info

Publication number: US3839592A
Application number: US00355891A
Authority: US
Inventors: A Freeman
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-04-30
Filing date: 1973-04-30
Publication date: 1974-10-01
Anticipated expiration: 1991-10-01

Abstract

A system is provided for automatically playing bass notes from accompaniment chords in a plurality of modes and also for playing bass notes with sustain in response to pedals. A scanner is provided to scan a selected one of two sets of playing controls and to stop and cause a bass note to sound when it encounters an actuated control. An automatic rhythm device is provided to restart the scanner for rhythmic modes. In non-rhythmic modes, the scanner is restarted when any control is actuated after the control which stopped it is released. The system also includes a controllable ratio frequency divider to minimize the number of pins required for an integrated circuit pack to implement the system for an electronic organ. Controls are further provided to select any of the following playing modes: A. All chord notes sounded in bass in ascending pitch order. B. All chord notes sounded in bass in ascending and in descending pitch order without repeating highest and lowest pitch notes in succession. C. Highest and lowest pitch notes of chord sounded alternately in the bass. D. Bass notes sound with or without sustain in normal response to operation of pedals. E. Lowest pitch note of chord sounds in the bass.

Description

United States Patent 1191 1 Freeman Alfred B. Freeman, 20418 Seaboard Rd., Malibu, Calif. 90265 [22] Filed: Apr. 30, 1973 [21] Appl. No.: 355,891

[76] Inventor:

[52] US. Cl 84/1.0l, 84/103, 84/DIG. 12 [51] Int. Cl. 61% 1/00 [58] Field of Search ..84/1.01,l.03,1.13,1.17,

84/1.24, 1.26, DIG. 2, DIG. 12, DIG. 22

[56] References Cited UNITED STATES PATENTS 3,546,355 12/1970 Maynard 84/103 3,548,066 12/1970 Freeman 84/103 3,549,774 12/1970 Bunger 84/103 3,567,838 3/1971 Tennes et al. 84/l.0l 3,610,799 10/1971 Watson 84/].01 3,707,594 12/1972 84/].03 3,708,602 l/1973 Hiyama 84/103 OTHER PUBLICATIONS D. O. Pederson et 211., Introduction to Electronic Systems, Circuits, and Devices, Copyright 1966 by McGraw-Hill, Inc., pp. 191-193.

Primary ExaminerRichard B. Wilkinson Assistant Examiner-Stanley J. Witkowski MANUAL KEYBOARD [57] ABSTRACT A system is provided for automatically playing bass notes from accompaniment chords in a plurality of modes and also for playing bass notes with sustain in response to pedals. A scanner is provided to scan a selected one of two sets of playing controls and to stop and cause a bass note to sound when it encounters an actuated control. An automatic rhythm device is provided to restart the scanner for rhythmic modes. In non-rhythmic modes, the scanner is restarted when any control is actuated after the control which stopped it is released. The system also includes a controllable ratio frequency divider to minimize the number of pins required for an integrated circuit pack to implement the system for an electronic organ. Controls are further provided to select any of the following playing modes:

a. All chord notes sounded in bass in ascending pitch order.

c. Highest and lowest pitch notes of chord sounded alternately in the bass.

d. Bass notes sound with or without sustain in normal response to operation of pedals. e. Lowest pitch note of chord sounds in the bass.

9 Claims, 3 Drawing Figures PEDAL KEYBOARD I MANUAL PEDAL 1 M 1 co & m:

PATENTEDUCT H974 BACKGROUND OF THE INVENTION 1. Field of the Invention This invention is directed to an improved system for playing bass notes from pedals and from accompaniment chords accordingto a plurality of modes.

2. Description of the Prior Art My US. Pat. No. 3,548,066 discloses a system for playing bass notes automatically in a plurality of modes. One of these modes uses a scanner to play all of the notes held in an ascending pitch order. The system could be operated by playing keys or pedals but could not be changed from one to the other without changing at least twelve connections. The system further uses large capacitors to store keying voltages for sustain as in a conventional organ pedal system. Such capacitors are expensive and cannot be implemented by an integrated circuit.

US. Pat. No. 3,567,838 to Tennes and Kern discloses a system for playing the highest and lowest pitch notes of accompaniment chords alternately in the bass. Playing may also be restricted to the lowest note only. No provision is provided to play all notes of the chords in bass nor to play bass notes in response to pedals.

Pedal sustain keying systems of present electronic organs typically use electrolytic capacitors to store keying signals so the bass signal can be sustained after the pedal is released. When a new pedal is operated, the capacitors must be discharged to terminate the sustain and avoid a possible clash between the old and new bass notes. The pedal switches are wired in interlocking fashion to prevent more than one bass note from sounding at a time when the players foot inadvertantly operates more than one pedal. Such systems have an appreciable cost.

It is an object of the present invention to provide a system for automatically playing bass notes from manually held accompaniment chords in a plurality of modes or patterns.

A further object of the present invention is to provide a system of the aforementioned type which can further respond to pedals for normal organ bass playing.

A still further object of the present invention is to provide a system meeting the aforementioned objects which can be implemented by an integrated circuit pack requiring a minimum number of pins.

Other objects and advantages of the present invention will become apparent as the description proceeds.

BRIEF SUMMARY OF THE INVENTION In accordance with the invention, an improved system is provided for automatically playing bass notes in response to manually held chords and also for playing normal organ bass in response to pedals. Means are provided for scanning each of the playing controls of selected manual or pedals one at a time in turn. Means are provided for stopping the scanning means when it encounters an actuated playing control. Means are further provided for producing a bass note while the scanning means is stopped, with the note produced corresponding to the actuated playing control which caused the scanning means to be stopped by the stopping means. Means are also provided for sensing when any control is actuated after the control which caused the scanning means to stop is released. Means are also further provided for restarting the scanning means responsive to said sensing means or to a signal from an automatic rhythm device. Still further, means are provided for controlling the scanning means in different ways to play bass notes in different rhythmic patterns or modes.

In the illustrative embodiment, playing control outputs for the same note in different octave locations from a manual and a set of pedals are connected together to an input for the note. A manual pedal switch connects the set of octave keying busses for manual or pedals to the scanning means which energizes the connected busses one at a time turn while scanning the note inputs. The producing means keys tone signals corresponding to the note inputs on which the scanning means stops and divides the keyed signals by the proper ratios to produce bass notes in the octave ranges corresponding to the energized keying busses. This arrangement provides a considerable savings in the number of pins required on an integrated circuit pack implementing the system.

In the illustrative embodiment, bass notes corresponding to actuated playing controls are sounded in sequence in order of ascending pitch by having the scanning means run in one direction and having an automatic rhythm device restart the scanning means in a rhythmic pattern. Bass notes are sounded in ascending and descending pitch order without successive repeat of the highest and lowest pitch notes by having the controlling means reverse the scanning direction after each cycle and cause the first actuated control after each reversal to be skipped. The highest and lowest pitch notes are sounded alternately in the bass by having the controlling means also reset the scanning means before each restart and change of direction. These different modes provide a variety that adds to the musical value which can be obtained from the automatic playing.

Also in the illustrative embodiment, bass notes corresponding to the lowest pitch playing controls actuated can be played without automatic rhythm by having the scanning means reset and restarted only by the sensing means. If no other control is actuated when the one for which a bass notes is being played is released, the scanning means will remain in position and maintain the bass signals so they may decay naturally. If another control is actuated, the scanning means will terminate the old signals and go immediately to the new note. This mode thus provides for normal organ bass playing with sustain from pedals, or lowest note in bass from manual. Pedal switches need not be wired in series for interlocking as the scanning means allows only one bass note to play at a time under any circumstances and electrolytic capacitors are not required to provide sustain.

The system will be most often used with an electronic organ or the like which can provide the manual, pedals, tone signals for keying, bass circuit, and sound transducer. Integrated circuits in a single pack can perform the other functions for the system.

A more detailed explanation is provided in the following description and claims, and is illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS; 1A and 1B connect together to form a partial schematic and partial block diagram of an embodiment of the invention.

FIG. 2 is a schematic diagram of part of the manual and pedal keyboards and their interconnections in the apparatus of FIG. 1A.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENT In the apparatus of FIGS. 1A and 1B, manual keyboard 11 is the accompaniment manual or keyboard section of an electronic organ or other musical instrument. Keyboard 11 has a multiple octave range but controls for the same note in different octaves are tied together so each note has a single output. Each of the 12 note outputs is connected by a resistor 12 to the input of an associated NAND gate 13. All 12 outputs are also connected to the NOR gate 14. Pedal keyboard 15 is a normal pedal keyboard of the type used in electronic organs and the like. Keyboard 15 covers a two octave range but controls for the same note are tied together so it also has only one output for each note. The twelve outputs from keyboard 15 are connected to the respective inputs from resistors 12 for the same notes.

Keyboard 11 receives keying voltage inputs for three octave keying busses via lines 16a, 16b and 160 from pedal manual selection switch 17. Keyboard 15 likewise receives keying voltage inputs for two octave keying busses via lines 18a and 18b from switch 17. With switch 17 in the position shown, lines 18a and 18b are connected to lines 19a and 19b respectively from octave decoder 20, and lines 16a, 16b, and 16c are connected to a negative potential supply. With switch 17 in its other position, lines 18a and 18b are disconnected and lines 16a, 16b, and 160 connected to lines 19a, 19b, and 19c respectively. Decoder 20 applies a positive voltage to each of lines 19a, 19b, and 19c in turn to enable controls in the respective octave ranges of keyboard 11 or keyboard 15 to produce a positive voltage output when actuated. Decoder 20 may also apply a positive voltage to all of lines 19a, 19b, and 190 at the same time.

Actuation of a playing key or pedal in an octave range having a positive keying voltage applied through switch 17 will enable the one of gates 13 for the associated note and willoperate gate 14. Gate 14 may consist of a combination of circuits which produce a negative output when any of the 12 inputs are positive. Resistors 12 prevent playing key actuation from interfering with response to pedals when switch 17 is in the pedal position and accompaniment chords are being played on keyboard 11. Pedals will not normally be actuated when switch 17 is in the manual position as bass will then be obtained from keyboard 11.

Note decoder 21 applies a positive voltage to only one of its 12 output lines 22 at a time. Each line 22 goes -to an associated one of gates 13 and an associated one of NAND gates 24. If a gate 13 is also receiving a positive voltage input for its respective note from keyboard 11 or keyboard 15, its output will go negative when its line 22 goes positive. The outputs of gates 13 all go to NAND gate 23 and the output of gate 23 will go positive when any of its inputs go negative. Gates 24 each receive a tone signal input corresponding to their associated note and pass it to NAND gate 26 while their input line 22 is positive. The outputs of

gates

23 and 26 go to NAND gate 27 which will pass the tone signal only when the corresponding gate 13 is operated causing gate 23 to have a positive output.

Up and down counter 28 provides four digit outputs to run note decoder 21 and two digit outputs to run octave decoder 20. The output of octave decoder 20 advances from one octave to the next each time note decoder 21 cycles through its 12 note outputs. Counter 28 may be stopped in any position and a positive voltage will then be maintained on the corresponding one of lines 19a, 19b, or and the corresponding one of lines 22. Control of the running and stopping of counter 28 will be described later.

The digit outputs from counter 28 to octave decoder 20 also go to OR gate 30 on lines 29a and 29b. Lines 29a and 29b will both be negative when counter 28 is positioned for the first, or lowest, octave. Line 29a will be positive and line 29b negative for the second octave. Line 29a will be negative and line 29b positive for the third octave. Flip flop 31 receives the output of gate 30 on its reset input and will be held in its reset position while the input is positive. Flip flop 32 has its reset input connected to line 29b and is similarly held in the reset position while the input is positive.

Tone signals from the output of gate 27 are applied to the toggle input of flip flop 31 and to one input of NAND gate 33. If its reset input from gate 30 is negative, flip flop 31 will change state with each cycle of the signal from gate 27 and enable gate 33 during alternate cycles. Gate 33 then passes alternate cycle and so a signal which is half the frequency of the signal from gate 27. If its reset input is positive, flip flip 31 will remain in the position which enables gate 33 and the output from gate 33 will then be of the same frequency as that from gate 27. The output of gate 33 goes to the toggle input of flip flop 32 and to one input of NAND gate 34. Flip flop 32 and gate 34 operate in the same manner as flip flop 31 and gate 33 so that the input frequency is passed unchanged when line 29b is positive and halved when it is negative.

The output of gate 34 is applied to the input of bass circuit 35 and will correspond in frequency to the output of gate 27 when line 29b is positive. The output will be two octaves lower than the output from gate 27 when lines 29a and 29b are both negative and one octave lower when line 29a only is positive. The frequency of input to bass circuit 35 will thus correspond to the note and octave positions of counter 28. Bass circuit 35, which may be substantially the same as percussion bass circuits in commercially electronic organs, such as the Lowry TBO model includes frequency dividers, tone forming circuits, controls, and keyers and has its output connected to output system 36. Output system 36 includes at least a power amplifier and a sound transducer.

RHYTHM OFF/ON switch 37, UP/UP-DOWN switch 38, and ALL/ONE switch 39 can provide different operational responses for the remaining apparatus and thereby obtain different playing modes. The first mode considered will be that for the switches in the positions shown which is the OFF, UP, and ONE positions for

switches

37, 38, and 39 respectively. If switch 17 is in the pedal position, bass notes will be played in response to pedal actuation in the normal manner including bass sustain. If switch 17 is in the manual position,

a bass note will play for the lowest pitch playing key actuated.

NAND gate 40 is held enabled by a positive voltage from an arm of switch 37 and the output of OR gate 411 is held positive to enable NAND gate 42 by a positive voltage from an arm of switch 39. When counter 28 reaches the position of an actuated playing key or pedal, the output of gate 23 goes positive. This output from gate 23 causes gate 40 to produce a drive to turn on the keyers of bass circuit 35 and gate 42 to produce a drive to reset flip flop 43. Reset of flip flop 43 disables NAND gate 44 to block the output of clock source 45 from the set input of counter 28. Counter 28 then stops on the position for the actuated playing key or pedal and bass circuit provides output signals for the corresponding note to sound transducer 36. This condition obtains as long as the playing key or pedal remains actuated.

When the playing key or pedal is released, the output of gate 23 goes negative. This turns off the drive from gate 40 to the keyers and the signals from bass circuit 35 begin to decay at a rate dependent upon control settings and parameters. The negative signal from gate 23 also goes through inverter 23a and enables NAND gate 46. Gate 46 is already receiving a positive voltage on its other input from flip flop 43 and immediated produces a negative output to set flip flop 47. The voltage from flip flop 47 on line 58 to octave decoder 28 then causes a positive voltage to be applied to all output lines 19a, 19b, and 190.

If any playing keys or pedals, depending on the position of switch 17, are actuated, gate 14 will operate and cause a positive voltage output from inverter 14a to NAND gate 49. Gate 49 is already receiving a positive voltage on its other input from flip flop 43 and so immediately produces a negative output to inverters 50 and Si which are connected in cascade to the set input of flip flop 43. Gate 52 is also driven to reset counter 28 and the keyers of bass circuit 35. Inverters 50 and 51 provide a short decay to insure the resetting of the keyers and counter 28 will be accomplished before gate 49 is turned off by the setting of flip flop 43. The setting of flip flop 43 also resets flip flop 47 to remove the voltage on line 58 and restore decoder to its normal condition responsive to counter 28 and further enables gate 44 to pass the signals from clock source 45 to the step input of counter 28. Counter 28 then resumes scanning at arate dependent on the frequency of output from source 45 which is high enough to avoid any appreciable decay in reaching any actuated control.

Flip flop 53 is held in the reset condition by the negative voltage applied to it from an arm of switch 38. Counter 28 thus runs in the direction for an ascending pitch order only. As it is also reset before each restart, counter 28 always stops first for the lowest pitch control actuated. if no other control is actuated, the keyers of bass circuit 35 will turn off the signals for the note with normal decay. The note will thus not continue to sound although counter 28 remains in the same position until another control is actuated.

lf rhythm switch 37 is next placed in its ON position, the output from gate 49 will be replaced with the output from automatic rhythm 54 on line 55, and gate 48 will receive its enabling input from line 56. Each pulse out on line 55 will set flip flop 43, if it was reset, and reset counter 28 and the keyers of bass circuit 35. Counter 28 will then run until it finds an actuated control which causes gate 23 to operate. Operation of gate 23 will reset flip flop 43 as before and stop counter 28.

With gate 23 operated, gate 48 will be enabled and the keyers of circuit 35 will be responsive to pulses on line 56 to sound the corresponding bassnote. The corresponding note can thus be sounded in any selected rhythmic sequence while the control is held actuated.

If switch 38 is next moved to its UP-DOWN position, the voltage holding flip flop 53 in the reset condition will be removed. Each reset of counter 28 will then cause flip flop 53 to change state in response to an output from octave decoder 20. The input from flip flop 53 to the up down input of counter 28 then causes it to alternately run up and down as flip flop 53 changes state. if a plurality of controls are actuated, notes corresponding to those of the lowest and highest pitch will alternately be sounded in the bass. If only a single control is actuated, the same note will sound repetitively as the counter 28 will simply reach the same position each time from alternate directions. The alternation of flip flop 53 may be momentarily interrupted by a pulse output on line 57 from automatic rhythm 54 which will force the lowest pitch note to sound at particular times, such as the downbeat.

If switch 38 is returned to the position shown and ALL-ONE switch 39 placed in its other position, gate 52 is disabled so counter 28 and the keyers of circuit 35 are no longer reset by automatic rhythm 54. Gate 41 receives its positive input through the series combination of an arm of switch 39 and an arm of switch 38. Each pulse on line 55 thus starts counter 28 and each operation of gate 23 stops it. Bass notes corresponding to actuated controls will then be sounded in turn in order of ascending pitch with the sequence being repeated as long as the controls are held actuated.

[f switches 39 and 38 are both in different positions than those shown, the positive input to gate 411 will be removed. It is then necessary for gate 41 to receive a positive voltage input from flip flop 59 to enable gate 42. Gate 42 must be enabled to allow operation of gate 23 to reset flip flop 43 and stop counter 28. The output from decoder 28 which triggers flip flop 53 to change state when counter 28 reaches its reset position also resets flip flops 59 and 68. The next operation and release of gate 23 then changes the state of flip flop 68 to the set condition and this in turn sets flip flop 59 so it povides a positive voltage to gate 41. The next operation of gate 23 and succeeding operations will stop counter 28 until flip flop 59 is again reset. The first actuated control encountered after each change of direction thus does not stop counter 28. If this were not done, the highest and lowest pitch notes would each be sounded twice in succession.

It will be recognized by those skilled in the art that the apparatus in many models of electronic organs would require only minor modifications to serve as the keyboards llll and 15, bass circuit 35, output system 36, and automatic rhythm 54 of FlGS. IA and 11B. It will further be recognized by those skilled in the art that the remaining circuits of FIGS. 1A and 18; aside from

switches

117, 37, 38, and 39; could be implemented by discrete component circuits, by available integrated circuits, and by a custom designed integrated circuit in a single package. Those skilled in the art may make minor changes to the system to better adapt to particular implementations.

The blocks labeled note decoder l2, octave decoder 28, and up down counter 28 represent apparatus which is well know to those skilled in the art. Texas Instruments Incorporated of Dallas, Tex., among others, produces medium scale integrated circuits which function as decoders and up down counters. Examples are Up/- Down Binary counters SN 54191 or SN 74191 and Decoder/Demultipliers SN 54154, SN 74154, SN 54155, or SN 74155.

FIG. 2 shows keyboard 11 to have playing keys 101 which mechanically couple to operate their respective switches 102. Playing keys 101 may also operate other switches not shown and not associated with the bass system. Each of switches 102 for the same note in different octave locations are connected together to one end of an associated resistor 12 as shown for the notes C and C Lines 160, 16b and 16a are shown connected to the keying busses for switches 102 of the first second, and third octaves respectively. If playing keys 102 for the same note in two octave locations are actuated at the same time, the associated switches 102 will connect the busses 16a, 16b, or 16c together so both will be energized when either receives voltage from scanner 20. This will cause the corresponding note to sound in both octaves, as it should, if switch 39 is in the all position. Notes for actuated playing keys 101 in either octave will also sound in both octaves. This is not believed to be a defect which would justify placing a diode in each lead from a switch 102.

Keyboard 15 has pedals 103 mechanically coupled to switches 104. Lines 18b and 18a connect to the keying busses for the first and second octave ranges respectively. Switches for the same note in both octave ranges are connected together and to the other end of an associated resistor 12 as shown for the notes C and C Resistors l2 isolate switches 102 from switches 104 so busses 16a, 16b, and 16c may be connected to a negative supply and playing keys 101 actuated without affecting the response to switches 104. It is not expected that pedals 103 will be actuated except when it is desired to produce bass notes from them but playing keys 101 will be actuated to play accompaniment chords whether or not bass notes are to be played from them.

What is claimed is:

1. in an electronic musical instrument having a set of playing controls for the notes of a musical scale and an output system including a sound transducer, an improved bass playing system comprising the combination of:

a. means coupled to said playing controls for scanning each of said playing controls in turn, said scanning means having an individual position for each of said playing controls;

b. means coupled to said playing controls for sensing whenany one of said playing controls is actuated;

c. means connected to said sensing means for enabling said scanning means to run when any one of said playing controls is actuated;

(1. means coupled to said scanning means for detecting when the one of said playing controls for which said scanning means is positioned is actuated;

e. means connected to said detecting means for stopping said scanning means when said detecting means finds an actuated playing control; and

f. means connected to said scanning means and said detecting means for producing a bass tone signal to drive said sound transducer, said bass tone signal being for a note determined by the position of said scanning means.

2. The combination according to claim 1 including an automatic rhythm device producing output signals in rhythmic patterns and means coupled to said scanning means for restarting said scanning means in response to a signal from said automatic rhythm device while said stopping means is operated.

3. The combination according to claim 2 including means connected to'said scanning means for controlling the direction in which said scanning means runs through its positions.

4. The combination according to claim 3 wherein said controlling means responds to each operation of said stopping means to reverse the direction of said scanning means.

5. The combination according to claim 4 including means connected to said scanning means for resetting said scanning means to a predetermined position each time said scanning means starts to run.

6. The combination according to claim 3 wherein said controlling means reverses the direction in which said scanning means runs each time said scanning means reaches a predetermined position.

7. The combination according to claim 6 including means connected to said stopping means for inhibiting its response to the first operation of said detecting means after each change of direction by said controlling means.

8. The combination according to claim 1 wherein said producing means includes a controllable ratio frequency divider for shifting the octave range of the output from said producing means, said frequency divider being controlled by said scanning means to divide by different ratios while different octave ranges of said playing controls are being scanned.

9. The combination according to claim 1 wherein said playing controls are comprised of first and second groups connected in parallel to said scanning means,

said first and second groups being energized one at a time by said scanning means, said detecting means being responsive only to actuated playing controls of the one of said groups which is energized.

Claims

1. In an electronic musical instrument having a set of playing controls for the notes of a musical scale and an output system including a sound transducer, an improved bass playing system comprising the combination of: a. means coupled to said playing controls for scanning each of said playing controls in turn, said scanning means having an individual position for each of said playing controls; b. means coupled to said playing controls for sensing when any one of said playing controls is actuated; c. means connected to said sensing means for enabling said scanning means to run when any one of said playing controls is actuated; d. means coupled to said scanning means for detecting when the one of said playing controls for which said scanning means is positioned is actuated; e. means connected to said detecting means for stopping said scanning means when said detecting means finds an actuated playing control; and f. means connected to said scanning means and said detecting means for producing a bass tone signal to drive said sound transducer, said bass tone signal being for a note determined by the position of said scanning means.

3. The combination according to claim 2 including means connected to said scanning means for controlling the direction in which said scanning means runs through its positions.

9. The combination according to claim 1 wherein said playing controls are comprised of first and second groUps connected in parallel to said scanning means, said first and second groups being energized one at a time by said scanning means, said detecting means being responsive only to actuated playing controls of the one of said groups which is energized.