DE2318881A1 - INTEGRATED CIRCUIT FOR AN ORGAN SYSTEM WITH FULL HARMONIC WAVES, INCLUDING A DEVICE FOR FLUTE TOE AND PEDAL TOE - Google Patents

Description

2318851

for eight octaves of the manual tones and three octaves of the t6-foot, 8-foot and 4-I ¹ ua-pedal tones or equivalent. Each Sehaltkreis requires only one audio frequency input or clock for each of two "adjacent tone groups, e.g. one for G and one for G φ '■. The integrated circuits are LSI circuits (large scale integration) and contain frequency dividers, the arrangement to provide for sampling and the circuit stages _{Eechteckwellen?} for collecting and controlling the outputs for the octave or half octave filtering and for the Formantbildung, and three Eedalausgänge ,, one for each of the _16-S Iuß- 8- and 4-foot Pedal tones or the equivalent for other applications - Ee gate precautions have been taken for phase synchronization of the frequency dividers.

Background of the invention

Field of the Invention "-" "" ■ - '". -

The invention relates primarily to the effective adaptation of the techniques of integrated MOSFET circuits (metal oxide-silicon field effect transistor) for the production of LSI circuits for a light wave (fully harmonic wave) organ system with gates for flute tones (sine waves)., The system delivers also 16, 8 and 4-5 ¹ US pedal tones of the light wave type. The system is such that each circuit (which are all identical) has octave-related groups of two adjacent tones

so that six circuits all for a manual of Keys provide required sounds including those required for the pedal keys ". In the LSI circuits if precautions have been taken for keying, step switching, frequency division and output mixing, see above that the only input signals required are two bars, one for each of the "adjacent tone octave groups. The outputs are mixed so that the number of circuit connections is a minimum. A novel scheme is also created, to filter the outputs of several circuits in octave groups so that sine waves despite the Fact that the system is basically of the fully harmonic wave type. The system can be used for this be to deliver all the tones of an organ and it becomes simplicity halter essentially described as "; it has true- ■ ■ but apparently its greatest usefulness is to increase the possibilities of an organ, which also other sound sources of a different kind.

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-A- Summary of the Invention

S = Oi = SSSS = SSSSSS = SSSS = S = S = E = SS S = SS = S = SS = S =

Heli wave organs, which are also known as organs with fully harmonic waves or formantorgein, are based on the Principle that, starting from fully harmonic waves, the Containing fundamental frequency and a generally decreasing series of both even and odd harmonics, these waves formanted (filtered and resonated) can be used to produce a wide range of tonal characteristics to achieve. Fully harmonic waves of the most useful type for the starting point are sawtooth curves. These can thereby are described as having a practically very short rise time and a straight-line fall or vice versa.

One way to create fully harmonic waves is that one starts from square waves that only have the fundamental frequency and have a decreasing series of odd harmonics, and add an octave-related series in a manner that commonly known as tapping. This becomes one. Square wave with the frequency of the fundamental wave by an octave The higher-lying square wave with half the voltage level is added, plus the square wave two octaves higher with one Quarter of the level plus the three octaves higher square wave with an eighth of the voltage level. The addition

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of four square waves balanced in an octave relationship creates an ¥ elle with a series of small steps, which approximates a real sawtooth very well. This stair wave can be fox coated to make a number more useful To give musical answers, however, is not an option for octave-wide filtering for the production of sinus xirelles, as they are needed for the flute tones. The reason for this is, that every sinusoidal filter must pass the basic waves, the second and must, however, exclude all higher harmonics. The number of tones that can be filtered together is therefore strict limited, and therefore a large number of rather expensive filters are required.

The usual way is to filter the pike-wave to remove everything except the fundamental, instead of starting from the fully harmonic wave, since in the square-wave the closest harmonic to the fundamental has three times the frequency of the fundamental, and so each filter can contain one tone octave _y which covers a range of only two to one, usually fully harmonic waves are achieved by stepping square waves »and the most convenient arrangement for the delivery of audio signals, at all the audio frequencies required by the instrument, sees twelve main frequencies or

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Measures for the top octave of the instrument and divides each of these twelve frequencies to get the closest octave, etc. The most reliable and generally preferred circuit for this binary division, especially when identical circuits are to be used at very different frequencies, is this Flip-flop that supplies a square wave as an output signal. It is therefore a Torteil _it's present in all the different frequencies as a starting point for the full harmonic waves or light waves to be used _s the square waves received. ₈

If, an LSI circuit is _s mix stage circuit and keying used for the frequency division in einem.einzigen circuit, therefore, a problem is ₉ perform another feed line set of the circuit case of the sources of the square waves for the sine wave filtering out ^ without the terminal capacitance of the switching housing su Overstrain »The present invention solves this problem, among other things, by making separate outputs for square-wave audio signals superfluous _s and it achieves this _s by providing only one additional connection compared to those _s required for the delivery of the step-switched waves ₉ .

Certain features of the present specification are also included in the U-Patent 3636 231, issued on 18/01/72 to Ray and David B.Schrecongost Millet entitled "Synthesis DCKeyed organ Employing to Integrated Girsuit".

Brief Description of the Drawings ■

The existing from Figures 1A and 1B! Ig. 1 is a Schematic representation of an LSI for carrying out the present invention for two groups of adjacent, in octave relation standing tones, especially the G and C # tones in the present example

Fig. 2 is a schematic representation of a complex wave probe, which forms part of the! "ig. 1," for synthesizing of step waves from square waves, and

Pig. 3 is a schematic representation of the complex in which Pig. 1 ¥ eller push button system used to set a group of 16 ', To deliver 8 'and 4' pedal tones or equivalent.

Description of the preferred embodiment

The terminology is correct in this description and in the drawing and the symbols correspond to what appears to be common in the LSI field. Circuit arrangements on the LSI plate, with known goals are not described or shown in detail. These details are not necessary for an understanding of the invention and were the

Extend and complicate the description unnecessarily. Usually circuit elements used, such as flip-flop frequency dividers that divide by 2, buffers that compensate for changes in signal level, Erase circuits' to reset the flip-flops to zero or another start position when a pulse hits one with the flip-flops connected line, gates that open or close depending on the potential on a line, among other things, are only described in the form of the functions that they perform. Connections. however, between such elemmites are shown and described.

The system uses LSI circuits which are all identical and which each provide two sets of tones spaced a semitone apart and in octave relation. To be precise, the circuit to be described provides all G and C # tones. Another supplies the D and Djf tones, another the E and E; ^, tones, etc. Each circuit supplies eight octaves of these tones, from C ₁ to C _fi and C # ₁ to C ^ „for example and also three octaves of 16 *, 8 · and 4 'pedal tones or the equivalent for both G and C $ , up from the 16'C tone with ^r its fundamental at C .. Although these are here as pedal tones they can of course also be connected for other purposes. The distinguishing feature is that it is separate

Circuit output terminals for the 16 ', the 8 ¹ and the 4' tones.

As shown in Fig. 1, the C-tone system takes the left side of the ! Figure on, and the C /. Tone system the right side. As the circuits are identical with the exception of some common parts, only the circuit for the C tones will be described in detail.

In the upper part of the I ¹ Ig. 1, a terminal 100 is connected to a C-clock which is outside the circuit. This C-clock delivers an input signal with 4186 Hz, ie C ".

The connection 100 is connected via a buffer 1o2 to the line 1o4, which in turn is connected to a binary frequency divider flip-flop 1o6. The output 1o8 of the divider 1o6 is connected to a second divider 11o. Its output 112 is connected to a third divider 114. This divider cascade is continued by adding additional stages designated 118, 122, 126 and the lines between the stages are designated 116, 12o, 124 and 128, respectively. The output of the last stage 150 has the identifier 132. The frequencies that are available on the individual supply lines are, if musical terms are used: Line I04: G ₀ , 108: G “, 112: C ,,, 1i6s G ,. ,

b / ο 5

120g Ο ,, 124s G ^ ₉ 128? Gg and 132g CL. All of these audio frequencies

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are square waves and have roughly the same peak voltages. The buffer at 1o2 compensates for possible voltage changes in the C-clock relative to the outputs of the frequency divider.

A terminal 154 is connected to line 138 via a buffer 136 connected to each of the frequency dividers I06, Ho, 114, 118, 122, 126 and 13o is connected. This is an extinguishing system and resets all frequency dividers to a uniform starting position whenever a pulse of correct polarity is applied to terminal 134 ~ '. If the present system alone would provide all the tones of an organ, this extinguishing system would not be required. However, since the organ still has other Sources for the same sound, it is necessary that E.g. the C-tones of all sources are in phase with each other in order to avoid cancellation effects. Therefore some source provides e.g. one of the C-tone sources in another part of the system not described here, a periodic pulse, preferably at half the frequency of the lowest musical note Terminal 134 »· of all C-tone systems in uniform starting positions resets. Therefore the C-tones of all sources are in phase with each other. Once they are in phase, they stay usually also in phase with each other. Accordingly, the Syrichronization system becomes usually only when the instrument is switched on

required to bring all frequency dividers to a zero starting position. The same system is used, of course, to _t, the synchronization of the other tones ensure.

In connection with this characteristic will be special to the still pending US patent application I84 81 ο by Ray B. Schrecongost with the title "Integrated Circuit Synthesis and Bright Wave Organ System" by the same applicant in which this feature is referenced will be discussed in greater detail.

A group of eight keying blocks I40 is shown under the frequency divider decade just described. These blocks are identical to one another and are shown in greater detail in FIG. They differ from each other in the tone they are touching. These blocks I40 therefore have additional individual designations, namely beginning on the left · · with G ₁ JC ₂ , Oy C ₄ , C ₅ , C ₆ , C ₇ and G _ß .

According to FIG. 2, the key block HO has a feed I42 for. the negative voltage Tdd, which is low resistance with the sinks of four HOSFST slement I44, I46, I48 and I50 is connected. The gates of these Slemente have feeders that start with F (fundamental wave), 2F (double fundamental), 43? (fourfold fundamental) and 8F (eightfold

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Fundamental wave) are designated. The source of the MOSFET 144 is connected to the drain of another MOSFET element 152, the source of which is connected to a button output line 154. Each of the other elements 146, 148 and 150 is ^au f Similarly, connected via a second mittelohmigen MOSi ¹ 15 ^ ET "158 and I60 with the output of I54. The gates of elements 154 »15 ^, 158 and 160 are connected to one another and to the keying terminal 162.

Outside the LSI circuit, play button contacts 164 » which are actuated by the corresponding play key for the sound, a corresponding keying potential from a source 166 to the Terminal 162 on. A desired cover former 168 can be used in order to give this tactile potential the appropriate enclosure. It can be steady and by a simple opening and closing of contact I64 has been created or removed, or it can be a holding or pushing envelope. Key wrapper for this purpose are well known and need no precise description here.

- The button works as follows. It is assumed that an appropriate square wave signal of the desired fundamental frequency for the tone is applied to line S ¹ , and that the square waves with double, quadruple and eightfold fundamental '

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frequency corresponding to the lines 2F, 4S ¹ and 8F are applied. Under these conditions, these square waves applied to the gates of the MOSFETs will chop the Ydd DC potential and apply the obtained square waves to the MOSFSTs 152, I56, I58 and 160. When the play button actuating contacts I64 "is pressed, the resulting potential with the desired envelope applied to the gates of MOSFETs I52, I56, I58 and" causes these elements to conduct and apply the mixed square wave signals to output I54.

At the time of manufacture, the geometry of the I10SFHT elements is chosen so that, when actuated, the effective resistance through the elements I46 and I56 in series is twice as great as that through the elements 144 and ¹¹ ^. 152, which through I48 and I58 is four times as large as that through I44 and I52 and that through I50 and 1βΟ eight times as large as that through I44 and 152. The mixture of rectangular waves therefore forms a step that approximates a fully harmonic light wave. In a typical configuration 55.B. the MOCFETs 144, 146, 148 and I50 can have a resistance of 100 ohms and the MOSFETs I56, I58 and I60 a resistance of 10, 20 or 40 kOhm.

The key pad for C. is with its F line with the C .. line 132, while the 2F line is connected via a MOSFET gate I70

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with the G_ line 128, the 4F line with the C, line 124 -and the 8F line is connected to the C. line 120. That Gate I70 prevents the CL frequency from being sent to the 2F line of the Keyboard block is created, unless a corresponding Potential is applied to the gate control line 172.

All other keying blocks I40 for C_, · C, C ,, C, C ,,, C ,, and C ₀

d. 3 4 5 ο ι σ

are connected in a similar manner. That is, "in any case the F line receives the fundamental frequency, the 2F line receives twice the fundamental frequency, and so on, and in either case the 2F line is over a gate I70 connected, whose control small with a control line 172 is connected, which in turn is connected to a circuit connection 174 is connected.

One exception is that the Cg keypad has no connection to its 8F line, the C ₇ -BIoCk has no connection to the 4F and 8F lines, and the C ₀ -BIoCk

is only connected to the F line. At the highest contained Frequency (8372 Hz or above) is itself the lowest of these missing harmonics not noticeable enough to justify the extra expense. "You would provide require an additional frequency divider in the cascade and a clock with 8374 Hz.

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As mentioned, the C ^ part is a doubling of the and for the sake of simplicity, the same reference numerals have been used for the elements to avoid confusion avoid, only certain key names have been introduced. Suffice it to say that the Cj ^ clock terminal 100 is a Receives CjiCj frequency at 4435 Hz. For the sake of clarity

the musical tone frequencies Cj #., CA. etc. on the lines and recorded on keypad I40. The keypad outputs 154 are drawn with gates I70 in the 2F lines, and these gates are also connected to gate control line I72, which leads to terminal I74.

The various button outputs 154 are connected as follows. A circuit connection I76 is connected to lines 154 for the keying blocks C ₁ , Cp, Cj ^. and C / _p connected. Terminal I78 is connected to lines 154 for key blocks C, and C /,. Similarly, outputs I54 are for blocks C. and

VJ /. with the terminal 180, which is for C ₁ . and C / _ with terminal 182, ·· 4 - Jj

those for C, - and C / ^ with terminal I84, those for C "and C /" with whether 'Jl

of terminal 186 and those for C ₀ and C ^ _{n are} connected to terminal 188.

By combining the outputs in this way within the LSI, only seven circuit connections are created for the sixteen

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_ Sounds needed. The output terminals I76, 178, 180, 182, 184, 186 and 138 are connected to the output system of the instrument via the usual formanting circuits and also via sine filters, which have a pass band of have a little more than an octave. If fully harmonic Eell-wave tones are desired for the formanting, the potential applied to terminal 174 is such that all gates I70 are switched through so that the second harmonic and the odd harmonics of the second are contained in the stair-step mixture which is at the outputs 154 of the key blocks is present. On the other hand, if solder tones are desired, such a potential * - is applied to terminal 174 that all gates I70 are disabled. Under these conditions, the mixture at the button output terminals 154 contains the fundamental frequency and all harmonics normally present in the stair-step wave, with the exception of the second harmonics and the odd harmonics of the second. As a result, the mixed output is missing the second, sixth, tenth harmonic, etc. It is important that the second harmonic is missing and the harmonic closest to the fundamental frequency is the third harmonic contained in the square wave ^{applied to the probe input line I 1}

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Although this output waveform is more complex than the original Hechteckwelle is the so far "preferred Welüaaform for the Filtering is in the production of flute tones, filtering is no longer difficult because the closest frequency is removed must be of the connection with the fundamental frequency, in both cases three times the frequency of the fundamental frequency. By Adding just one port 174 for controlling all of them second harmonic, the circuit delivers both full harmonics Stair-step waves for formanting as well as waves that can be satisfactorily filtered into octave groups To deliver flute tones (sine waves) by simply using the potential is changed at a single circuit terminal 174. The waveform control described can also be used for other tone changes with or without filtering may be useful by removing other square wave components the staircase switch can be controlled.

For this section of the circuit, the circuit supplies and samples 8 octaves of two adjacent tones (e.g. G and G $ ) in both fully harmonic form and in a form suitable for filtering to produce flute tones, only the following circuit connections being necessary : Ground and two voltage terminals, usually labeled Ydd and Tgg ¹ , to connect the

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MOSFET circuit elements to operate, plus two inputs for the two clocks and two clear inputs, plus seven output terminals, the sixteen connections 162 for the game key circuits and a single terminal 174 for controlling the second sarmonic, making a total of only $ 1 circuit connections for sixteen Results in tones and two different waveforms. That is concerning the connection requirements extremely economical, especially when it is taken into account that sixteen of the connections for the>: Connection with the Eontakt systems of the sixteen game keys of the instruments operated by the circuit are required.

The systems for keying and supplying the 16'-, O ¹ -, 4'- for the two adjacent halftone groups (θ and G ^ - in this example) are similar, and therefore the description of the left system for the C tones suffices. A keying system 200 (iPig.j) for the low G consists of three groups of keying blocks of the type shown in! 2, one each for the 16 ', 8' and 4 ^f tone. A play key connection 2o2 controls all three blocks so that they all key together when the play key for the low C is pressed. Similarly, the Vdd voltage line 142 is connected across all three key blocks. The outputs of the three blocks provide separate output ^{terminals for the 16 * -, the 8 1} - and the 4 'tones at 2o4 »2o6 iazw. 2o3 ·.

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Each of the three Sastungsblocks has four Musiktoii-üignaleinga.ngs-Terbindungen ϊ ?, 23 ?, 4I = 'and 31 for the fundamental frequency and the double, the fourfold "and the eightfold the fundamental frequency. Tucks are connected as follows: the G, .- Line 132 is connected to F of the Lö 'key block; the Cp line is connected to 2Έ of the 16' block and P of the 8 'block; the G, line is connected to 4Ϊ ^{1 of} the 16' block, 2Έ of the 8 'block and]? Of the 4'block; G. is connected to 8Ϊ of the lo 'block, 4E "of the 8' block and 2F of the 4 'blockj G- is connected to 8F of the 8' block and 4F of the 4 'block and C, - is at 8Γ of the 4' block. ·

When the play button for low C is pressed, all twelve buttons in the three blocks emit stair-step waves at a distance of one octave from the three outputs 2o4 »2o6 and 2o8 for the 16 ·, 8 ^f and 4 'fully harmonic wave tones 'through, based on C ₁ for the 16' tone.

Another set of buttons for 16 ', 8' and 4 'G tones that are around an octave higher than the group for the play key for low C, is shown at 210, and a third movement for one C two octaves higher is displayed at 212. tuck Button groups are the same as the groups described above, with the exception that all sound signal jülaganes leads by an octave for

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the group 210. and shifted up two octaves for group 212. The individual 16 ', 8 ¹ - and 4' outputs of _a i ± _{en of} these groups are connected to the same I6 ^r , 8 · and 4 'output terminals 2o4, 2o6 and 2o8, respectively.

The same arrangement is shown in the right half of the I ¹ Ig, 1 for the three groups of 16 ', 8' and 4 'G ^ r iPones. The outputs of the Gj ^ part of the circuit are connected to the same connections as the G part of the circuit, so that all 16'-G and Lö'-Cj ^ tones in the three octaves appear at the same connection 2o4. Similarly, all 8 'and all 4' tones appear at terminals 2o6 and 2o8, respectively.

This system therefore adds to the circuit the ability to ^{supply and key three octaves of fully harmonic 16 f} , 8 'and 4' pitch tones for two adjacent semitones, G and C $ 'in this particular example, and requires the addition of only one additional control circuit connection, six for C and $ 0 game key lines and three output connections for the 16 ', 8 · and 4' outputs.

Patent claims!

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Claims (11)

-21 claims / to generate i Λ integrated circuit "from one another in octave relationship stationary tones for an electric musical instrument, both in vollharinonischer form and in a form which is suitable for i'ilterung practically in octave groups to JFlötentöne, characterized by a substrate. Circuits on it, which form a binary divider chain, an input for the chain for receiving a clock frequency, the divider chain supplies a number of Reehteokwellensignen that are successive binary parts of the clock frequency, a number of button groups, each consisting of a number of individual buttons, the so are connected to one another that they are brought into a conductive state for passing a signal from each button input to its output when a button potential is applied to a terminal, which is connected to all buttons in this group, each of the buttons in a group having input connections the chain has in the way, 'that, we nn a keying potential is applied to a group, one of the buttons in the group conducts a pike wave with the fundamental frequency at a desired tone, another a pike wave at the second harmonic of this tone and a third "a square wave at the fourth harmonic of this tone, a Device that has a common output for the push-button 309845/0423 'Each group provides, -wherein the effective relative resistances the buttons of each group are selected so that the mixed signal at the common output of the group is a stair wave forms, through gates in the connection between the divider— chain and the common output through the button for the second harmonic in each of the groups, with the gates in. Dependency from the voltage applied to an element of the gate, are conductive or blocked, and by a circuit connection, which is connected to all of the latter gate elements in order to open or close all these gates together. 2. Circuit according to claim 1, characterized in that the Gates are in the connections between the buttons for the second harmonic and the divider chain. 3 · Circuit according to claim 1, characterized in that the Substrate clock input connections, divider chains and a number of groups of buttons for two octave groups of tones that make up a semitone are apart, and that the button group outputs for Tones that are a semitone apart within the circuit are connected to each other. 9845704 2 4. A circuit according to claim 2, characterized in that the substrate clock input connections, divider chains and a number Groups of buttons for two octave groups of tones that have a half tone are apart, and that the button group outputs for tones that are a semitone apart, within of the circuit are interconnected. 5 · Circuit according to claim 1, characterized in that additional button groups on the substrate are connected to the divider chain, the last-mentioned button groups being connected to the chain to 4 ¹ - »8 '- and - 16 ^! -To deliver stair-step tone outputs for at least two octaves. 6. Circuit according to claim 2, characterized in that additional button groups are connected to the substrate with the plate chain, the latter groups of buttons being connected to the chain to 4'- »8'- and I6 ^f -stair step tone outputs for at least two octaves deliver. 7. A circuit according to claim 3, characterized in that additional groups of buttons are connected to the substrate with the divider chain, the latter groups of buttons are connected to the ICette to 4 ¹ -, 8 'and lo' stair tones for 309845/0423 to provide at least two octaves of two groups of tones that are within a Ilalbton apart, wherein the switching circuit 4 ¹ - "S ¹ - comprises or 16'-Auegänge - and 16'-output terminals common to all 4'» S ¹ . S-. Integrated circuit for delivery and keying of in Octave relation to each other for an electric one Musical instrument in different waveforms ,, labeled through a substrate with circuits on it that form a binary divider chain, an input for the chain for supplying a clock frequency, wherein the divider chain supplies a number of square wave signals which are successive binary parts of the clock frequency are, a number of button groups, each consisting of a number of individual buttons that are connected to each other that they can be brought into a conductive state by letting a signal pass from each pushbutton input to their output, when a keying potential is applied to a terminal that is connected to all buttons of a group, each button being one Group has such input connections with the chain, 'that if a Keying potential is applied to a group, the keys of this group a number of square waves in octave relation to each other through a device that forms a common output for the buttons in each group, the 309845/0423 effective relative impedances of the buttons in each group like this are staggered that the mixed signal ad common output each group forms a stair wave through gates in the connection between the divider chain and the common output via one of the buttons in each group, the gate depending on the voltage applied to an element of the gate is applied, conductive or blocked, and through a circuit connection, which is connected to all of the latter gates in order to open or block all gates together. 9 · Circuit according to Claim 8, characterized in that the Gates lie in the connections between the buttons and the divider chain. 10. A circuit according to claim 8, characterized in that the substrate clock input connections, divider chains and a number Has button groups for at least two groups of tones, each of these groups comprising several octave-related tones, and that the button group outputs for at least some of the notes in the same octave within the circuit are connected to each other. 309845/0423 231888! 11. Circuit according to claim 9, characterized in that the substrate has clock input connections, I'eilerketten and a number of button groups for at least two groups of tones, each of these groups ^{comprising several tones in octave relation 1} , and that the button group outputs for at least some of the Tones in the same octave "are linked together within the circuit. 12, circuit according to claim 8, characterized in that · additional groups of buttons are provided on the substrate, which are connected to the control chain, the latter groups of buttons being connected to the chain by 4'- »8'- ^tm d 16'- To provide stepped on outputs for at least two octaves. 13 «Circuit according to Claim 9, characterized in that additional button groups are provided on the üubstra / b, which are connected to the divider chain, the latter i'astergruppen connected to the chain to 4 '-> 3 'and lo' - 'step tone outputs for at least two octaves. 14 · Circuit according to Claim 10, characterized in that Additional groups of buttons are provided on the substrate, which are connected to the cable chains, the latter being the latter 309845/0423 Groups connected to the chains to provide 4 '-> 8 ¹ - and 16 ^f - staircase tones for at least two octaves of the tone groups, a semitone apart, with the circuit having 4S S ¹ and 16' output terminals that are common are for all 4'- »8 ¹ and 16 'outputs. lieipa / Bre 309845/0423 ι "** · ♦ Read 11 e