DE2252653B2 - SIGNAL SELECTION SYSTEM FOR AN ELECTRONIC KEY MUSIC INSTRUMENT - Google Patents

Description

Keys with the same tone name is the same bistable 15; with one corresponding to the number of octaves Switching element can switch; with 12 tone switch set of button selection circuits in each octave group the outermost of the simultaneously closed

Select the key switch and let the corresponding bistable switching element tip over.

In a known signal selection system of this type for an electronic musical instrument (DT-AS 14 72 451) a number of circuits containing bistable switching elements is required which corresponds to the number of key switches corresponds, whereby the signal selection system

circles that transmit the audio signals when activated by the bistable switching elements; with a multi-stage frequency divider that halves the frequency per stage and the one with the outputs 20 the sound circuitry is connected; with a set of corresponding to the number of octaves Key selector circuits, which in each octave group the outermost of the simultaneously closed key switches select and the corresponding 25 is relatively complex and thus expensive, let the bistable switching elements tip over, characterized in that in addition an octave selection device (5) is provided which selects the outermost of the octave groups, and by the fact that it can tip over other bistable switching elements (11, 12) that control the power supply of the remaining octave groups switch off when the other bistable switching elements of at least one, with the key switches and the 12

The invention is based on the object of Giunde Signal selection system for an electronic keyboard musical instrument according to the type mentioned at the beginning create that in a cost-saving manner the required number of bistable switching elements for the entire range of keys forming several octave groups is minimized.

This object is achieved according to the invention in that an octave dialing device is additionally provided.

bistable switching elements coupled, detector 35 hen, you selects the outermost of the octave groups.

(6,7,8), which determines which octave groups are actuated by the fact that they have further bistable switching elements

were received, a signal, the other bistable switching elements also the number of active divider stages of the frequency divider (3, 4)

determine and wherein the detector delivers a further signal when the buttons are released, which all resets bistable switching elements.

2. Signal selection system according to claim 1, characterized in that the octave selection device (5)

comprises at least two detectors (6,7,8) which determine with 45 and wherein the detector delivers a further signal when the keys connected to the corresponding octave groups are released, which are illegal bistable to indicate the closing of any key switch (K, to Ku, Km to K _M , K ^ to K _3b ) in it and then to block the operation of the octave groups that are less far out. 50

3. Signal selection system according to claim 1, characterized in that the twelve bistable switching elements (1) consist of flip-flop circuits.

overturns elements that switch off the power supply to the remaining octave groups when the others bistable switching elements of at least one, with the key switches and the 12 bistable switching elements coupled detector that determines which octave groups have been activated, receives a signal, in addition, the further bistable switching elements the number of active divider stages of the frequency divider

4. Signal selection system according to claim 1, characterized in that the further bistable switching elements (l 1.12) consist of flip-flop circuits.

5. Signal selection system according to claim 1, characterized in that the at least one stage comprehensive frequency divider (3, 4) consists of a flip-flop circuit.

The invention relates to a Signalwählsysteni for a electronic keyboard musical instrument that, when several keys are pressed at the same time, of the keys associated tone signals resets the highest or lowest switching element.

The octave selection device advantageously has at least two detectors, which are associated with the corresponding Octave groups are connected to detect the closure of any key switch therein and then to block the operation of the less distant octave groups.

The twelve bistable switching elements and the other bistable switching elements can be made from flip-flop scarf lines exist and the frequency divider comprising at least one stage can consist of a flip-flop circuit exist.

The advantage of the invention is therefore in particular the reduction in the number of required bistable switching elements and the associated reduction in susceptibility to interference in the signal selection system. The invention will now be explained in detail with reference to the description of the drawing. In the latter are

F i g. 1 is a block diagram of a signal selection system according to the invention for an electronic keyboard musical instrument and

F i g. 2 shows a circuit arrangement of an embodiment of the signal selection system according to the invention.

F i g. 1 shows a block diagram of the invention Signal selection system that the signal selection system is suitable for an instrument having a number three Has octave groups forming keys

The keys can operate a number of key switches Kt to AC ₃₆ , which are divided into three groups 31 (K \ to A ₁₂ ), 32 (Kt) to Κγ.) And 33 (K ₂ S to K *,) according to each octave group. In the case of the key switches assigned to each octave group ι ο, the break contact of the latter is connected to a movable contact of the subsequent key switch in order to enable the signal to be selected when a number of keys are pressed at the same time. On the other hand, the working contacts of each of the key switches Kt to Ku assigned to an octave group are each connected to the working contacts of the key switches Km to AC ₂₄ , K25 to Ky, assigned to the same tone designation in the other octave groups, i.e. the key switches Kt, Kt% and AC ₂ S as well K2. ACw and AC ₂₆ etc. are connected to each other.

A circuit! has twelve bistable switching elements, which are assigned by the tones of an octave Buttons are switchable and each z. B. consist of the usual flip-flop circuit. The tone generators 2 supply the tone signals assigned to an octave, each tone generator 2 is associated with the corresponding one of the twelve Flip-flop circuits connected and the switching on and off of the sound signal is according to the State of the flip-flop circuits controlled.

The applied to a terminal 20 via the circuit of the bistable switching elements 1 of the circuit 1 The frequency of the audio signals is halved by a multi-stage frequency divider 3, 4 per stage. In In accordance with an octave selection device 5, the audio signal is either sent directly via a Galter 13 or passed through the divider stage 3 to the divider stage 4.

The octave selection device 5 has three detectors 6, 7 and 8 which are arranged so that the detector 6 or 7 or 8 responds when any key switch ACi to AC12 of the first group 31 or any key switch ACu to AC _{24 of} the second Group 32 or any key switch AC ₂₅ to AC _{36 of} the third group 33 is closed.

The oval selection device 5 also has two unstable switching elements 11 and 12, which are so are arranged that the bistable switching element 11 overturned by a pulse from the detector 7 and is switched back by a pulse from the detector 6 and that the bistable switching element 12 by a Pulse from detector 8 is tipped over and switched back by pulses from detectors 6 and 7. When the bistable switching element 11 has flipped over, the gate 13 is conductive and that at the terminal 20 The audio signal lying on the ground is skipped directly to the divider stage 4 of the frequency divider 3, 4 passed, so that at terminal 23 as a result of the frequency halving by the divider stage 4, a tone signal half the frequency compared to the audio signal at terminal 20.

A further gate 14 is provided which is conductive when the bistable switching element is overturned, and the audio signal on terminal 20 goes directly to terminal 23 without passing through the frequency divider 3, 4 so that the frequency of the audio signal at terminal 23 is the same as that of the audio signal at terminal 20 will. If the two gates 13 and 14 are blocked, the sound signal applied to terminal 20 is via the Divider stage 3 and then passed through the divider stage 4, so that the tone signal occurring at terminal 23 a Has frequency that is equal to a quarter of the frequency of the audio signal at terminal 20

The octave selection device 5 also has two circuits 9 and 10, which are normally conductive. The circuit 9 is connected to the detector 6 via a diode D12 and is switched off by the operation of the detector. The circuit 10 is connected to the detectors 6 and 7 via diodes Dn and D _! switched off

If a detector 22, which is connected to a terminal 21, detects the closing of the buttons, then it sets all flip-flop circuits in the circuit back, thereby only sending one selected audio signal to the Terminal 20 is supplied.

F i g. 2 shows a circuit arrangement of an embodiment of the signal wave system according to the invention, with elements of FIG. 1 matching elements have the same reference numerals and the Circuit 1 and the tone generators 2 are inclined as a block. The mode of operation of the signal selection system goes out following description. The number of bistable switching elements and tone generators is equal to twelve, corresponding to the number of tones in an octave, and there is a flip-flop circuit for that Divider stages 3 and 4 of the frequency divider 3.4 are provided. The divider 3 halves the frequency of the audio signal, and the divider stage 4 in turn halves the frequency of the audio signal coming from the divider stage 3.

The detectors 6, 7 and 8 consist of the transistors Tu, Tib and Tj ?. If the key switches (K ₁ , K ₂ to AC ₁₂ ) or 32, (AC ₁₃ , AC ₁₄ to AC ₂₄ ) or and (AC ₂ S, AC ₂₆ to AC ₃₆ ) of group 31 or 32 or 33 are closed, the transistors Ti5, Ti ₆ and T ₁ , respectively; saturated. Saturation indicates that the key switches in each group are closed.

The other bistable switching elements 11 and 12 also consist of flip-flop circuits with transistors T ₂₁ and T22 as well as T ₂₃ and T ₂₄ . The bistable switching element 11 is overturned via a diode D \ _b when a positive voltage is applied to the collector of the transistor T _{16 of} the detector 7, and it is via the diode Di? reset when a positive voltage is applied to the collector of the transistor Ti _{5 of} the detector 6. The bistable switching element 12 is flipped over via a diode Dm when a positive voltage is applied to the collector of the transistor Tw of the detector 8, and it is via the diodes Di? Di8 or reset when a positive voltage to the collectors of the transistors Tu or T _{1 b} of the detectors 6 and is laid. 7

The anode of a diode D _{22 of} the gate 13 is connected to the collector of the transistor Ti of the bistable switching element 11 via a resistor Rib , and the cathode of the diode D ₂₂ is connected to the terminal 20. When the transistor T _{21 of} the bistable switching element ί 1 is blocked is, the diode D _{22 is} conductive and the divider stage 3 is bypassed, so that the audio signal from the terminal 20 to the divider stage 4 passes. When the transistor T _{2 of} the circuit 11 is saturated, the diode D _{22 is} blocked.

Similarly, the diode D21 of the gate 14 is conductive when the transistor T _{23 of} the bistable switching element 12 is blocked, and thus the divider stage 3 and 4 is bypassed, so that the terminal

20 audio signal is fed directly to terminal 23 will. Is the transistor T23 of the bistable switching element 12 saturated, then the diode D21 is blocked.

A capacitance Q differentiates the drop in the tone signal and supplies a negative pulse for triggering the divider stages 3 and 4 of the frequency divider, a negative pulse with the frequency of the tone signal being obtained at terminal 23.

If the frequency of the audio signal at terminal 20 is not changed, the audio signal at the terminal has 23, when both gates 13 and 14 are blocked, a frequency that is equal to that of the two octaves lower Tone signal is and when the gate 13 is conductive, a frequency equal to that of the one octave lower The sound signal is and the same frequency as the sound signal at the terminal 20 if the gate 14 Is riding.

The circuits 9 and 10 consist of transistors Tib and Ti, and resistors /? I ₈ and /? M, respectively. Normally, both circuits 9 and 10 are conductive due to the base current flowing _{through the opposing areas /? I 8} or A _1. At this point in time, the currents of transistors TIg and Ti become base currents of transistors Ti ₆ and Ti ₇ of detectors 7 and 8. However, the values of resistors R \ n and /? I are large enough and resistors /? N , and Ru are shunted to the base currents, so that the transistors Ti 1 and Ti _{7 of} the detectors 7 and 8 are not saturated.

When the transistor Ti? of the detector 6 is saturated, the strobe flowing through the resistor R] ₆ flows from the collector of the transistor T ^ via the diode Di ₂ , and the transistor Tie is thus blocked. Accordingly, the key switches Kn, Ku to K24 of the second group 32 are not supplied with any electrical power. Similarly, the circuit 10 is blocked when the detector 6 or 7 responds, so that the key switches K ₂ s, K _2b to K * of the third group 33 no electrical power is supplied.

If the detector 22 detects the moment the key switches close, then it switches all of them Flip-flop circuits of circuit 1 back, so that only one audio signal can be selected to the terminal

got.

The octave selection device, which consists of the detectors 6, 7 and 8, the circuits 9 and 10, the further bistable switching elements 11 and 12 and the gates 13 and 14 determines the groups of key switches that contain the closed key switches, selects the key switches of the outermost ones the octave group that corresponds to the lowest or highest tone in these octave groups , and then interrupts the power supply to all key scarf octave group that corresponds to the opposite or highest tone signal.

As the action switch in each group of the key switch are in series, the signal selection is made for each group of key switches.

As an example, the signal selection for the first group 31 of key switches Ki, K ₂ to K12 and between the other groups is described below with reference to FIG. 1 described.

If z. B. the key switch K «is closed, a voltage applied to the terminal 21 is applied to a flip-flop circuit of the circuit 1 which controls the key switches Ki. K ₁₃ and K ₂ s is assigned, placed over the detector 22, the detector 8, the circuit 10 and the key switch Κ ₂ · ϊ, and this flip-flop circuit is switched. In this way, the key switch K ₂ -; corresponding acoustic signal to terminal 20.

On the other hand, when the detector 8 responds, the bistable storage element 12 is overturned and the gate 14 thus becomes conductive. For this reason, the acoustic signal is sent to terminal 20 unchanged to terminal 23.

If the key switches Ku and K ₂₅ are closed at the same time, the flip-flop circuit assigned to the key switches Ki, Kn and K ₂ - is switched again by the detector 7, the circuit 9 and the key switch Ki ₃ . On the other hand, the circuit 10 is blocked by the detector 7, so that the detector 8 does not respond. Current 30 flowing through detector 7 continues to reset bistable switching element 12, and bistable switching element 11 is overturned, whereby gate 14 is blocked and gate 13 becomes conductive. Accordingly, the frequency of the audio signal at terminal 20 is halved by the divider 4, so that the frequency of the audio signal at terminal 23 is half the frequency of the audio signal at terminal 20.

If the key switches Ki, Ku and K ₂₅ are closed at the same time, the flip-flop circuit assigned to these key switches is switched by the detector and the key switch Ki and the corresponding sound signal is switched on. On the other hand, the circuits 9 and 10 are blocked by the detector 6, so that no current flows to the detectors 7 and 8. As a result of this, the bistable switching elements 12 and 12 are reset and the gates 13 and 14 are blocked. The frequency of the tone signal at terminal 20 is therefore halved by the divider stages 3 and 4, so that a tone signal whose frequency is a quarter of the frequency of the tone signal at terminal 20 reaches terminal 23

The preferred constant generation of the lowest tone signal when closing a number at the same time Key switch can preferably be used to generate the

tern of the octave group, which in ggg

Direction from the selected outermost octave group. "" .. "v ..". ^. «,.,", ". ^^" ^ ", _"

If the octave selection device _S5 is activated, the highest tone signal is reversed, springs dfe Art

at the same time the Tefler stages of the frequency divider for triggering the circuits 9 and W and the gates

Generation of a sound signal with a frequency. «Fie the 13 and 14 of the signal heating system described Frequency of the outermost key on the keyboard that is little changed.

is pressed simultaneously, assigned lowest

For this purpose 2 sheets of drawings

Claims (1)

Patent claims: 1. Signal selection system for an electronic keyboard musical instrument, when several keys are pressed simultaneously from those assigned to the keys Selects the highest or lowest sound signals; with a power supply; with 12, the 12 tones of the tone generators corresponding to the highest octave; with a number of key switches, which are represented by a Number of keys comprising at least 2 octaves, i.e. at least 2 octave groups, d. H. at least 24 are operated; with 12 bistable Switching elements that can be switched by the keys assigned to the tones of an octave, with selects; with a power supply; with 12 tone generators corresponding to the tones of the highest octave; with a number of key switches that are divided by a number of at least 2 octaves, i.e. at least 2 octave-group-forming keys, i.e. at least 24 are pressed; with 12 bistable Switching elements that can be switched by the keys assigned to the tones of an octave, with keys same tone name same bistable switching element ment can switch; with 12 audio circuits that support the Pass on audio signals when activated by the bistable switching elements: with a multi-stage Frequency divider, which halves the frequency per stage and which is connected to the outputs of the audio circuits