GB2433155A

GB2433155A - String and button assembly for electronic musical instrument

Info

Publication number: GB2433155A
Application number: GB0525022A
Authority: GB
Inventors: Paul Mencher; Justin Mencher
Original assignee: BARRELHOUSE MUSIC Ltd
Current assignee: BARRELHOUSE MUSIC Ltd
Priority date: 2005-12-08
Filing date: 2005-12-08
Publication date: 2007-06-13
Also published as: GB0525022D0

Abstract

The present invention provides a string assembly 12 for a musical instrument 10, a finger button arrangement 14 and a control button assembly 90 for the same. The string assembly comprises a plurality of strings having portions 26 for interaction with the user and a second portion 28 for making electrical contact which causes initiation of a control signal arrangement to create a desired sound. The button arrangement may be used for chord or note control whilst the control button assembly may be employed to select chords or the like.

Description

MUSICAL INSTRUMENT

The present invention relates to musical instruments and relates in particular but not exclusively to musical instruments having strings, which are either plucked or hit either directly or indirectly by a person playing the instrument. There is disclosed a string assembly for a musical instrument, a finger button arrangement and a control button assembly for the same. Each of these elements may be employed as control means in applications other than musical instruments.

Learning to play a musical instrument is a difficult exercise for most people. The difficulties arise from the need to learn several essential and non-intuitive skills simultaneously in order to achieve a satisfactory sound. In a guitar, for example, a user must learn to hold the instrument correctly without tiring and also learn to pluck and strum the strings with the appropriate force whilst positioning the fingers on the neck of the guitar at the right places to stop the strings against the frets. Additionally, the user must maintain the guitar strings -tuning, replacing them when they break and re-tune them when necessary whilst also learning to read musical notation or tablature as well as develop a sense of musical tone and rhythm.

An aspiring guitar player must actually force their bodies to adapt to playing, a change which takes place only when the guitar is practiced frequently and consistently.

Thickening of the skin at the finger tips occurs in response to the painful process of pressing steel or hard nylon strings hard against the guitar neck is one problem and the hand and forearm muscles must develop or adapt as required in order to allow the player to stop the strings when necessary. This requires increasing flexibility of the hand and forearm so that the fingers can be positioned correctly on the neck and strengthening of the upper arm and neck muscles is required in order to support the arm that extends to the guitar neck.

With the resulting sore fingertips, stiff muscles and potential tendonitis, it is not surprising that most people give up before achieving a sufficient level of skill that they find rewarding.

A number of attempts have been made to make the playing or learning of a musical instrument more enjoyable and somewhat less difficult but none of these seem to have provided an acceptable solution to the above-mentioned problems.

The present invention is aimed at providing an improved apparatus and method of learning a musical instrument such as a traditional guitar or similar stringed instrument. It allows novices to play such an instrument in a relatively short period of time by bypassing or reducing many of the obstacles inherent in learning to play a traditional musical instrument. Whilst the examples within the present description relate particularly to stringed instruments those skilled in the art will appreciate that various aspects of the present invention may be applied to other instruments and, indeed, may be applied to other non-stringed instruments.

According to a first aspect of the present invention there is provided a string assembly for a musical instrument having a string, having a first and a second portion; a string deflection sensor for sensing deflection of the string; and a string mounting member for mounting said first portion for lateral motion upon being struck by a player.

According to another aspect of the present invention there is provided a finger button arrangement of electrical switches for an electronic musical instrument in which said finger buttons correspond to notes on a scale wherein said buttons are arranged in a trapezoidal configuration.

According to a still further aspect of the present invention there is provided a method of operating a stringed musical instrument of the type claimed herein having the steps of: detecting deflection of one or more of a plurality of strings; passing data relating to the deflection to a control device; and instructing an audio device to play a sound allocated to said string.

The present invention will now be more particularly described by way of example only with reference to the accompanying drawings in which: Figure 1 is a general view of a stringed instrument according to aspects of the present invention; Figure 2 is an enlarged view of a single string arrangement according to one embodiment of the present invention; Figure 3 illustrates an array of the strings shown in figure 2 which when combined form a string assembly; Figure 4 is a perspective view of the string anchoring arrangement at the electrical contact end thereof; Figure 5 is a perspective view of an alternative arrangement of string mounting; Figure 6 is a more detailed view of an alternative string arrangement in a deflected position, closing a contact switch; Figure 7 is a process flow diagram showing the method of operation; Figures 8a to 8c illustrate a method of measuring the magnitude of deflection of a single string arrangement in one embodiment of the present invention; Figure 9 is a perspective view of an alternatively mounted string arrangement; Figure 10 is a schematic illustrating a method of detecting various magnitudes of deflection in an alternatively mounted string arrangement Figure 11 illustrates the effect of a frictional force on a string assembly used in an embodiment of the current invention played using a bow; Figure 1 2a to I 2b illustrate an embodiment of a tensioning mechanism for the string assembly in the present invention; Figure 13 is a view of a string arrangement embodiment incorporating rigid sections connected by flexible joints or hinges; Figure 14 is a view of a rigid section string arrangement illustrating the geometric advantages of the configuration; Figure 15 is a general view of a finger button configuration according to an aspect of the present invention; Figure 16 illustrates a button arrangement suitable for achieving a third note or chord using a combination of two other notes or chords; Figure 17 illustrates one alternative arrangement of the finger buttons; Figure 18 illustrates a further alternative arrangement of the finger buttons; Figure 19 illustrates positioning of an additional finger button that facilitates switching between left-handed and right-handed players in one embodiment of the present invention; Figure 20 illustrates a configuration of the finger buttons for a left-handed person; Figure 21 illustrates a configuration of the finger buttons for a right-handed person; Figure 22 is a general view of the control buttons as envisioned in an embodiment of the present invention; Figure 23 is a schematic illustration of the range of motion of a typical human thumb on a stationery hand; Figure 24 is an enlarged schematic view of the notes played by a traditional guitar when the strings are stopped at the second fret; and Figure 25 is a diagrammatic representation of a piano keyboard.

Referring now to the drawings in general but figures 1 to 4 in particular, it will be appreciated that a stringed instrument 10 such as a guitar generally comprises a string arrangement 12 and a finger control portion 14. Conventionally, the string portion is generally mounted on the body 16 of the instrument 10 and extends along a neck portion 18 at which point the fingers of the person playing the instrument interact with the strings so as to affect a change in the note emanating therefrom. The arrangement of the present invention is similar in as much as the string arrangement 12 is positioned on the main body 16 whilst the finger control portion 14 is positioned on the neck 18. It will be appreciated that other arrangements are possible without departing from the spirit of the present invention.

Referring now more particularly to figures 2 to 4, it will be seen that the strings' simulate traditionally mounted strings in action and feel to the user and incorporate electrical switches which sense the deflection and transmit the occurrence of the deflection to the electronic circuit and the computing device, which responds appropriately. This innovation detects a string release -the event which triggers a string sounding in a traditional instrument -and conveys that to the computing device. The computing device then generates the programmed sound with a delay imperceptible to the human ear, effectively simulating the acoustic properties of a traditional tensioned string. The string simulator feels like traditional strings in tension and rigidity and react like traditional strings in physical response to being plucked or struck. Additionally, the arrangement is easy to assemble and maintain whilst being robust, simple and inexpensive to manufacture. The main feature of the string simulators is the design geometry. They are designed so that mechanical switches, which are simpler and often less expensive than electronic switches, can be used more effectively and at lower cost. It will be appreciated that an amount of variance is permitted in the manufacturing process. The less variance permitted, the more accurate and precise -and expensive -the manufacturing needs to be. Conversely, if lower tolerances (more variation) are permitted, the process can be less expensive. The string simulators are designed so as to require less precision in manufacturing, while retaining the sensitivity of traditional strings. One of the primary results of the design is to make sure that the deflection at the point of electrical contact (some distance away from the place where the string may be plucked) is sufficiently large so as to allow consistent detection by a mechanical switch or switches. If the deflection is relatively small (e.g. on a micro' scale) the mechanical switches to detect the motion must be made more precisely. However, for larger deflections, the accuracy required is less and the parts are easier to manufacture. Therefore, maintaining a relatively large deflection at the point of electrical contact is preferable. Another advantage resides in the fact that traditional long tension strings are replaced by a short string arrangement, thereby allowing the instrument to be hinged for easy transportation. This is certainly not possible with traditional instruments of this type.

Figure 2 shows two configurations of string side by side in the deflected position. For both strings 20, an electrical current is provided at anchor point 22 and a circuit is closed when the string 20 touches the contact 24 positioned towards one end of the string itself.

String 20a (dashed line) is a conventional electrically conductive, flexible string, held in tension and anchored at both ends. When deflected near the middle of its length (in the direction of arrow C) the string deform in an arc as shown and it returns to the centre resting position under its own tension. In contrast, string 20b of the present invention is composed of a relatively stiff first section 26 connected to a relatively flexible, conductive wire 28 at one end and an extension spring 30 on the other. When deflected, the stiff section moves laterally but remains straight whilst the spring extends and the flexible portion 28 flexes as shown, thereby allowing the stiff portion to move laterally from its rest position and significantly increasing the amount of deflection of the wire 28 at the contact point 24. A rubber collar 32 may be provided for damping of the string and, if provided, it prevents the string from overshooting the centreline and hitting the contact on the other side. It will be appreciated that by lateral movement we mean movement in a substantially parallel manner away from a rest position rather than an arcuate deflection as known in the prior art and illustrated in figure 2 herein.

There are several ramifications to the configuration of String 20b: 1. The greater deflection at the point of electrical contact (24) means that smaller deflections by the user at the playing area C will be detected, offering a more sensitive and realistic feel to the person playing; 2. The length of a string between the two suspension points is not required to be any longer than the length most convenient for the player -say 15-18 cm to offer a realistic simulation of traditional strings.

3. The shorter mini' string means that the rigid frame and long highly tensioned strings of a traditional instrument are no longer required -the whole assembly can be pocket-sized or smaller, while offering the same sound as a full-size assembly.

4. The stiff string section can be made from a non-conductive material or electrically isolated from the flexible wire (28), protecting the circuit from electrostatic shock.

5. Spring 30 can be changed in stiffness according to the users preferences.

6. Spring 30 can also be replaced by any other elastic material or tensioning mechanism with the same properties, such as rubber.

7. The gap between contact wire 28 and contact post 24 need not be unnecessarily small. With lower manufacturing tolerances (greater variance in final dimensions) the contact string may be slightly off centre. Furthermore, it is desirable to have sensitivity' when strumming the string, that is, how much one needs to displace the string before the contact wire makes contact with the contact post.

8. For the purposes of geometry, the string and wire contact could be made of materials that are either stiff or flexible depending on the configuration. Diagrams following in this document illustrate some of the other possibilities.

9. The purpose of the spring is to allow the string to deflect in the same way as a traditional string and to bring it back to its natural resting position. It also provides a small but important damping effect, the magnitude of which depends on its physical properties.

In the particular arrangement of figure 2, the strings 26 are arranged in an array, best seen in Figure 3. The arrangement includes a conductive, stranded wire 28 lying between electrical contacts 24 which when brought into contact with contact 24 and then released gives an indication that a string has been plucked. An extension spring 30 (as opposed to compression spring) brings the string 26 back to its central position after being plucked and reduces blow to fingers on impact. The contact post 24 is common to each string and may be provided on each side thereof and preferably above and below as shown in figure 4 later herein. A guide channel 34 on a fixed portion 37 centres the wire 26 between the contacts 24, ensuring that the strings have a consistent and reliable feel however they are strummed or plucked over time. The string portion 26 in the form of, for example, stiff piano wire does not vibrate unduly because of its stiffness in relation to the spring 30 and this helps limit vibration and noise caused by its low natural frequency. Damping may be provided in the form of a rubber or otherwise soft material tube 32 around the spring which dampens the vibration of the spring 30 and reduces any noise and also the bounce effect as any electrical contact is made. This arrangement (best seen in figure 12) also dampens the sound of spring coils hitting each other. A non-conductive eyelet connector 36 performs two functions. Firstly, it electrically isolates the string 26 so that the player's fingers are not directly connected to the circuit. Secondly, it can provide damping for any vibrational noise between rigid portion 26 and tensioning spring 30. The attachment does not significantly affect the operation of the whole system no matter how it is done. It could be glued, tied, stapled, hinged or welded, to name a few methods. The only constraint is that it should not adversely affect the desired geometry described above. In many circuits, it is desirable to have the circuit electrically isolated from the user. In such cases, either the material of the string portion 26 being plucked should be nonconductive, or the join between the string and contact wire should be nonconductive.

Figure 4 shows a close up of one form of the guide channel 34. The flexible portion 28 of the string wire rests in channel 34 before being routed down through a hole 40 to connect to the sensing circuit discussed later herein. The channel 34 positions the wire an equal distance between the contact posts 24 on either side so that the feel of the strings is reliable and consistent.

Additionally, if a conductive ring 24a is added to the configuration, lateral deflections in all directions can be detected. The magnitude of deflection can be can be detected by using a series of concentric rings of varying diameter, positioned along the axis of the resting flexible portion 28.

It will be appreciated that the properties of the string may be varied. For any material chosen for the string, a spring of different qualities (of stiffness, internal friction etc.) can be chosen to cause a different vibration and damping condition. It will also be appreciate that the spring could be a compression spring as opposed to the tension spring described above or any other such similar object which returns to its original position when deflected.

Figures 5 & 6 show alternative arrangements whereby the stiff rod section 26 that serves to simulate the string is mounted on a spring 50 at one or both of its ends. When the rod is deflected by the user (arrow C) an electrical pad 52a on the rod 26 makes contact with another pad 52b on the contact posts 24, closing an electrical circuit. Each string is mounted separately with its own circuit and so can be detected individually. Damping for the spring can be provided by damping material 54 (rubber, silicon, etc) surrounding the spring 50, within the spring or by a buffer between the spring and the contact post.

In operation, the contact wire 28 on the string' and the contact post 24 are the two terminals of a simple electrical switch which, in the resting position, are not in contact. In all arrangements of this invention, electrical contact is made when the string is deflected (strummed, plucked or hit by the user) and contact is broken when the string is released.

When contact is made, this information is read by the computing device (e.g. PC) by means of an electrical hardware circuit suited to the port to which it is attached (e.g..

USB, parallel port, serial port, Bluetooth wireless or any future replacements for these) The software can be programmed to play a sound for the string either when it makes contact or, more usually, when it breaks contact. The former would correspond to hitting the string so as to simulate a slap bass guitar, violin or percussion instrument, for example. The latter would correspond to plucking or strumming, as with other stringed instruments.

The change of the switch's state, from off to on, is represented by a bit in a memory byte and that information is transmitted to the software in the computing device, shown schematically at 99. Because the relevant event is the release of the string (when on a traditional instrument the string starts to vibrate and produce sound), the software waits until the contact has been broken until it plays the sound. Figure 7 shows a process diagram of the interaction between firmware in the electronic circuit, and the software on the computing device 99.

In the process flow diagram of the current embodiment, shown in Figure 7, the contact wire comes into contact with the contact post 24 when the string is deflected. If the software is in Pluck mode, it waits until the string is released and the switch is opened.

Otherwise it is in Hit mode and proceeds to the next step, to check if any previous sounds are still being played. If previous sounds are still being played the computer 99 stops the sounds played by that string, otherwise it proceeds to play the sound programmed for that string (step 4). However, unless otherwise instructed by a setting in the software, sounds generated from other strings would keep playing, as on a traditional guitar. The software checks to see if there are any modifications (step 5a) during the playing of that sound, such as pitch bend, volume or any other such change. If there are (step 5b) it makes the modifications to the sound. If no modifications, it continues playing the sound (step 6).

It is also possible to stop' the strings playing, as if damping the strings with the hand on a traditional stringed instrument, by assigning step 3b to a button on the guitar 10 or on the computing device 99. If the user presses it while the sound is playing, all sound would stop.

An important result of this arrangement is that once the string has been detected as being plucked or hit, the appropriate programmed sound is played by the software on the computing device. This sound is a recording or digital simulation of an actual physical string being played; because the sound plays with no detectable delay after the string is played, the presently described arrangement appears to have the same acoustic characteristics as the actual instrument from which the recording was made.

Volume control and detection may be achieved by an arrangement such as that shown in figures 8a to 8c, which show an arrangement which allows the detection of various degrees of deflection and therefore the equivalent volume in a physical string. In figure 8a the string 28 is deflected but only makes contact with a first 24a of a plurality of terminals and contact is detected by the circuit and the software is programmed to play a sound at low volume when 24a is contacted. In Figure 8b, the string 28 makes contact with terminals 24a and 24b, but not 24c and the software is programmed to play a sound at a middle volume. Finally in Figure 8c all switches are closed and the software plays a sound at the highest volume. The combination of electronic hardware and software driver changes a different memory bit in a byte for each contact post.

Other arrangements not in the current embodiment could be: * Increasing the number of switches so that the volume steps are more finely graded * Instead of separate circuits, each switch could be connected to ground via a different resistance. Deflecting the rod further would allow current to pass through a lower resistance at points B and C, resulting in a higher detected voltage. The higher voltage would be translated into a higher volume by the software. The current embodiment contains a chip which can detect voltage changes and which can be used in this way.

Graded detection of string deflection for perpendicular mounting is also an option. In the case where it is desirable to mount the string from the bottom, a modified configuration can allow the sensing circuit to detect the degrees of string deflection. In the embodiment shown in Figure 9, rigid rod 26 is mounted on an electrically conductive elastic component 60 which is mounted in a substrate 62 in a channel 64 between damping pads 66. The elastic component 60 is shown as a leaf spring but could be another type of spring or any equivalent elastic material. Electrical contacts 24a to 24c are mounted in the channel and connected to the sensing circuit (not shown).The schematic shown in Figure 10 shows how the arrangement can operate. Figure lOa shows the rigid string rod 26 mounted on an elastic component 60 which is electrically conductive itself or made so by combining with metal foil or wire, for example. As the string is deflected to the left (as in Figure lOb) the conductive component 60 contacts terminal 24a, but not 24b or 24c.

As the string is deflected further (as in Figure 1 Oc), it comes into contact with 24b, but not yet 24c. Finally, at its maximum deflection (as in Figure lOd), it contacts all three terminals 24a to 24c. It will be appreciated that the string operates in the same way with the equivalent terminals on the opposite wall when it is deflected the other way.

Additional terminals can be added in line with the others, to increase the precision of the detection of the deflection. The curvature of the channel walls and spacing of the fixed terminals can be varied to bring the deflecting conductive component 60 into contact with the fixed terminals 24a to 24c earlier or later, thereby changing the volume and duration signals for the string. Different curvatures would offer a different feel' to the player.

The present invention may also be extended to instruments such as violins, violas and cellos which are played with a bow that causes the tensioned strings to vibrate. The main variables which a player controls with the bow in such an instrument are the force and speed with which the bow is drawn across the strings which controls volume and the duration of which it is applied which controls the length of the note. If the deflective force is applied by the friction of a bow sliding across the spring as best seen later herein. A greater force applied to string results in a greater deflection; as shown above, this is related to the number of terminals which are in electrical contact with the deflected elastic mount. The duration may be detected by the length of time the terminals are closing the circuit and any variation during the playing of the note (which is very common in bowed instruments such as this) can be detected by the changing number of terminals in electrical contact with the conductive elastic mount.

Referring now to figure 11 we will explain the relationship between the frictional force and the operation of the bow in a little more detail. It will be appreciated that between any two surfaces sliding against one another there is a frictional force Ff called the sliding friction.

It depends on the magnitude of the perpendicular force pushing the two surfaces together (called the Normal force, EN) and the coefficient of friction between the two surfaces, .tf. In the diagram in Figure 11, a long object, represented by a violin bow 66, slides across the curved top of a string 26 from left to right.

The frictional force of resistance (Ff) is given by: Ff = FN X.tf Resisting this force is the spring that the string is mounted on. The resistive force offered by the spring is proportional to its dimensions and its spring rate. If the frictional force is stronger than that of the spring, the spring will deflect until it reaches maximum deflection.

Supported by the geometry of the mounting, the spring/ string force will increase and overcome the frictional force between the bow and the string at which point the bow will start sliding over the string. When the bow stops moving, or the musician reduces pressure on, or removes the bow, the spring will return the string to its resting position and disconnect the electrical contacts.

In the current embodiment, this result applies to the bow moving in both directions.

Damping of the strings may be necessary in order to take full advantage of the present arrangement. Damping is the tendency for friction to absorb the kinetic energy of an oscillating body and it plays a relatively important part in the operation of the invention because it controls the residual oscillations of the string 26, which could result in bounce' -the inadvertent and unwanted second or third closing of the switch on a single playing of the string. This would have the result that the system plays the sound of the string more than once. As will be appreciated from the above, the main section of the string 26 -the part that the user touches and strums, plucks or hits -is suspended between two points P (figure 2). The material used to suspend it must be elastic so that it can return the string to the centre resting point consistently. If the material itself does not have any damping properties, a damping mechanism may advantageously be added to the system.

There are several ways to reduce erroneous signals from the switch, for example: * Electronic Damping -The application software in the computing device and the firmware in the chip provide electronic damping byfiltering out any subsequent play' signals within a certain, configurable time window. That is, if more than one identical signal is received within that time window, it ignores them. By filtering out erroneous signals close to their source, the rest of the system is spared the overhead of processing them.

* Physical Damping from innate qualities of the materials -The rod section can be suspended with materials that have both elastic (can be deformed and returns to its original shape) and damping qualities. In this case, the spring would be replaced by a connector made of rubber or silicon, for example. This suspending material would provide both the elasticity and damping.

Physical Damping with damping components -Introducing external friction to the elastic tensioning mechanism. For example: Friction applied to spring or elastic element such as enveloping the spring (or other elastic component) in a latex tube, see example in present embodiment below.

Friction applied by inserting an elastic element in the centre of the spring A piston and cylinder attachment at the end of the string in order to produce friction in a viscous liquid such as oil.

An example of a suitable damping mechanism is shown in figures 1 2a and I 2b which show in more detail the arrangements shown in figure 2. In these examples the stiff portion 26 is connected to a spring by any suitable means and that spring is anchored by screw 68 to a ground portion 70 (best seen in figure 3). A close fitting tube 32 made from rubber or some such similar material suitable for the purpose is positioned around the spring 30 so as to cause frictional contact to be created between the spring and the tube as the spring deflects. This friction will, effectively, act as a simple form of damping and assist in the desire to reduce excessive string vibration.

Various types of string construction are possible and the properties of the strings and contact wires are only limited insofar as they affect the desired geometry or damping when used in conjunction with each other. There are therefore an unlimited number of combinations (stiff wire, flexible wire, soft strings, hard rubber etc). The combinations are bounded by two main constraints: geometry, and damping.

* Geometry -the string is displaced from its rest position by the finger (strummer) is equal to or smaller than the displacement of the string at the point of electrical contact * Damping -the damping of the combined system must be such that the string returns to its original rest position without making multiple contacts on subsequent oscillations of the string. Thus, a string with the right material properties could be used without the spring described in the current embodiment. Another desirable feature of the damping is that it limits the audible sound created by the various frequencies of the string, contact wire and spring combination.

Figures 12a and 12b show an embodiment incorporating a spring within a rubber tube, which acts as a damping mechanism by rubbing against the outer surface of the spring.

The same effect can be created using damping material in the centre of the spring.

An alternative string construction is shown in figure 13 in which a compound string comprising three rigid sections 70, 72 and 74 connected by flexible joints or hinges 76.

Section 70 forms one terminal of an electrical switch, in which when the central section 72 is deflected in the direction of arrow D, section 70 rotates around a fulcrum formed by walls 78 and comes into contact with a terminal contact 80 similar to 24 shown in the earlier drawings. This closes the switch and the system is thereby able to detect the deflection of the string and play the appropriate sound. The sections are allowed to move by means of pivot point 76 that anchors the assembly in place. Springs 84 not only push the assembly back to its natural resting position, but also help to suspend the central section in an appropriate position for the player. Damping of the assembly can be done with a rubber tubing covering the springs or in other ways, discussed elsewhere herein.

Figure 14 shows one of the main features of the above design. Referring to the labels in Figure 13, if the contact section 70 rotates on a fulcrum 78, the dimensions are related by the equation: L2 D2 = x D1 Li This implies that if L2 is greater than or equal to L1, D2 will be greater or than or equal to D1.

A traditional string, suspended between two points, deflects in an arc. When deflected at some midpoint, the displacement of the string from its resting position gets smaller, the closer to the end points you are. That is, its point of maximum displacement is at the point of deflection. Putting a detection mechanism at that point would interfere with the player, but putting it closer to the end points, out of the way, means that smaller displacements must be measured. The variability of manufacturing tolerances can make this expensive or difficult or both. This innovation magnifies the deflection being measured without changing the feel to the user.

Thusfar we have described a new string arrangement for use with musical instruments, each of which may be further controlled by some form of finger control which, in operation, is the equivalent of clamping a tensioned vibrating string to a given length so as to modify the note emanating therefrom. The present invention may also be provided with a finger button arrangement used to simulate the application of pressure on real strings by allocating a particular note to a given button provided at a convenient location on the musical instrument so as to allow the user control over the notes being played. A suitable arrangement is shown in figures 15 to 21 which illustrate the arrangement by way of example only. It will be appreciated by those skilled in the art that such a finger button arrangement may be used in any one of a number of applications other than musical instruments and that, consequently, the present invention is not deemed to be limited to the use of such an arrangement in a musical instrument.

By way of background, it is worth remembering that all notes in the traditional Western musical scale, whether played on a guitar, piano or another instrument are repetitions of a series of 12 notes, as shown in Table I and in Figure 25. This series of 12 notes or pitches' is called an octave' and repeats itself throughout the scale, with the pitches in all octaves having frequencies that are multiples of each other. Each note in every octave has an equivalent pitch an octave above and an octave below it. For simplicity, the notes can be best shown on a piano keyboard diagram (see Figure 25) showing a single octave (a guitar has the same notes as a piano does, but they are arranged differently). The major' notes are assigned to white keys and the minor' notes are assigned to black keys.

The minor notes can be referred to as the sharp' (#) of the note to its immediate left or the flat' (b) of the note to its immediate right. One can see that in this series of notes there is no sharp or flat note between E and F nor between B and C. In an octave to the right of the one shown in Figure 25 (i.e. higher in the scale), the next note is another C that is twice the frequency of the previous C. The note after that is a C sharp which is also twice the frequency of the previous C sharp... and so on. Likewise, in an octave to the left of the one shown (i.e. lower in the scale), the notes would be half the frequencies.

In the arrangement shown herein, the buttons are arranged on the neck of the guitar in two separate rows as shown in Figures 15 to 18 in which the buttons 80 are arranged in a trapezoidal configuration, that is to say arranged such that a first row 80a of buttons has one or more buttons less than the second row 80b and the buttons 80 of the first row 80a are displaced laterally relative to the buttons in the adjacent row. Each button is ascribed a note and, upon actuation connects an electrical circuit supplying current to the controller (computer) which causes the modification of the note to be played. Clearly, a number of button arrangements are possible and the examples of figures 15 to 19 offer a brief insight into some options in which the notes of a scale can be provided in order or in some other convenient arrangement. This arrangement has a number of advantages including: fewer buttons -adjacent buttons on the same row can be pressed simultaneously to achieve the sharp/ flat note in between, eliminating the need for five additional buttons, while retaining the ease of use for the player. In the above configuration, C sharp is accomplished by depressing both C and D at the same time, F sharp is accomplished by depressing F and C at the same time. Since there is no B sharp or E sharp, there is no need to depress buttons from the two rows at the same time in order to accomplish any of the 12 notes in a scale; ease of use -eliminating the need to move the hand along the neck by placing the buttons within easy reach of the fingers of a stationery hand. The combined depression of two buttons sends a combined signal to the controller which interprets it as a request for the ascribed sharp or flat note. The above configuration allows the hand to remain in the same position in order to accomplish all 12 notes/chords in the scale with the added feature of not having to push buttons at the same time which are on different rows. Additionally, there will be a significant reduction in learning time and fewer errors due to the need to remember fewer finger positions, all users will need less time to learn to play and make fewer errors when they are playing. There are several other configurations such as: transposing the order of the notes on the rows (see figure 18); transposing the order of the rows (figurel7); or a combination of the two. The buttons are used to control the software on the computing device, which translates their state into an equivalent physical configuration of, for example, a chord pattern on a traditional guitar, in readiness to play the sound. However, the use of software allows the buttons to be set in any configuration and offers a number of advantages such as allowing the user to configure buttons to suit their individual tastes or to tune buttons to different notes or chords. Additionally, such an arrangement allows the user to configure buttons for different functions altogether and allows user to switch simply between left-handed playing and right-handed playing as will be described later herein.

Most stringed instruments require strings that are suited for the tension and length of the note they are designed to play. This means that a low note will be played by a string which is more loosely strung and longer than that used for a higher note. On a guitar, the low E, is considerably thicker and looser than the high E and is constructed differently out of different materials. Traditionally, the strings of the guitar are arranged so that the low E string is mounted in the highest vertical position and the high E in the lowest, with the others in a specific order in between. This means that in order to change a guitar from being suitable for a left-handed person (who would have the guitar neck pointing to their right when playing) to a right-handed person (neck pointing left), one would need to remove all the strings from the guitar, replace the strings in the left-handed' sequence and re-tighten and re-tune the strings. With the instrument described herein, the system may be programmed such that the user merely clicks a button in the software and the change is made instantly. The present invention incorporates a button design that allows this to happen on a single instrument with no change in physical configuration. The arrangement may consist of two rows of offset buttons on the front of the guitar neck as shown in Figure 19 which is similar to the arrangement of figures 15 to 18 save for the addition of a further control button 82. Figures 20 and 21 shows how the buttons can be arranged to allow left-handed and right-handed users to play the same guitar without any physical rearrangement. The programmable buttons 82 can be changed from configuration A) (Figure 20)to B) (Figure 21) simply in the software. Marks + and o show the relative positions of buttons in both configurations and the grey trapezoid shows one of the button patterns described above. The button outside the trapezoid in either configuration could be any other user-programmable function or not used.

There are other chords related to the 12 mentioned previously, which are variations of those chords with a slightly different sound. In traditional instruments, these chords are formed by modifying (adding or changing) a note to the chord being played. However, these modifications can be numerous and complex and add more difficulty to an already complex task.

The present invention simplifies the selection of these modified chords by using the same modification (pressing of a button or buttons) for every chord. For example, whereas in a traditional guitar the modification of a C chord to make a G7 is different from the way a C chord is modified to make a C7 chord, on the guitar invention it is exactly the same (pressing the 7' button simultaneously with the chord button). This consistency of modification applies to all variations of chords, for example, minor, fourths, sevenths and elevenths, to name but a few standard ones. In the illustrated arrangement these modified chords are accomplished with buttons 90 on the back of the neck 14 of the musical instrument, although other positions and configurations are possible. There is a minor button 90a, a 7th button 90b and an 1th button 90c, the arrangement being such that only one of buttons 90b and 90c can be pressed down at the same time as button 90a. These modifier buttons are pressed simultaneously with the chord buttons to modify the chord selected. As arranged, some of the buttons can be pressed in combination with each other to give further chord modifications. However, there are certain permutations of buttons which, when pressed together would not give a meaningful chord instruction.

Pressing a chord button, a minor button and a 7th button would give a minor 7th chord (Cm7 for example) while pressing a chord button, a 7th button and an th button would have no meaning, It is useful therefore to arrange the buttons 90 in a configuration where the meaningful permutations are made easy for the user and the invalid permutations are discouraged or made difficult. This may be accomplished by employing a mechanical interlock or the software can be programmed to disregard or re-interpret any instructions generated by invalid button combinations (an electronic interlock). Together, these features constrain the user to producing valid sounds.

In practice, the minor button 90a is the only modifier button that can be pressed with any other button and it therefore needs to be easily accessible from all positions where other modifier buttons are pressed. In the illustrated example of figure 22, this is done by arranging the modifier buttons 90a to 90c so that the minor button 90a is proximate to all other modifier buttons, either by elongating the minor button, by arranging the other modifier buttons around it or a combination of these. Ergonomically, the best arrangement is to require as little movement from the digit pressing the modifier buttons (in this case, the thumb) as possible, while allowing for sufficient differentiation between the positions so the user can feel where they need to place their thumb. A small post 92 positioned in the centre of an arc of buttons 90a to 90c preferably arranged as segments of a circle and contoured or textured buttons 90a to 90c can all be used as a physical reference to aid navigation. This configuration encourages the user to press appropriate combinations of buttons, for example, 90a+90b or 90a+90c, but not 90b+90c. This is a useful arrangement if buttons 90b and 90c activate, for example, 7I and I 1111 variations of the chord and button 90a effects a minor chord.

The schematic diagram in figure 23 shows the reach of a thumb 94 whose base joint is approximately at the black dot 96 and which can rotate an angle of 8. The pad of the thumb (the primary point of manipulation) can effectively access only the two arc-shaped zones 98 and 100 without moving the hand significantly. By placing the minor button 90a in one zone 98 and the other modifier buttons in the other zone 100, the user can easily press valid combinations of buttons in a consistent way which is easy to learn. Minimising the movement of the hand is important because each time the hand moves, the user must re-orient the fingers, increasing the cognitive overhead and making playing more difficult.

It is also possible through software modifications to organise combinations of buttons to accomplish the same effect. For instance, one could accomplish a C minor by pushing the C button on the top row of figure 19 and any other button on the lower row. This is a great advantage of the design that any number of button configurations can accomplish the same thing merely through changing software. The present arrangement means that any buttons, knobs, switches and pedals used can be placed anywhere and used to control the software through wired or wireless communication with the computing device.

Buttons on a wired or wireless pick/ plectrum are possible, as are buttons, switches and knobs on the guitar body or switch or knobs on a foot pedal (not shown). Allowing the player to use other limbs and digits to control the guitar reduces the cognitive overhead and dexterity required from the hands and fingers. This makes it easier for the novice user to play competently. Buttons can be placed on the back of the neck or on top of the neck or in a position midway between the two.

One purpose of the present arrangement is to provide a small number of switches to easily represent a large number of chords. The 7 buttons represent the 7 major notes of a scale (C, D, E, F, G, A, B). Modifications to these 7 root notes are made in a consistent and easy to learn way for all notes. A flat note is obtained by depressing said button corresponding to that note and also the adjacent said button to the first button that is lower on the musical scale whilst a sharp note is represented by depressing said button corresponding to that note and also the adjacent said button to the first button that is higher on the musical scale. Thus, we have 12 notes or chords that can be represented by 7 buttons. The buttons are arranged in two short rows because they are easier to cover with four fingers without changing the hand position. Further modifications of chords (over and above the 12 described) can be achieved with consistent and simple buttons configurations. For instance, a minor' button for minor chords can be pressed along with any of the previously described 12 chords to produce another 12 minor chords whilst a button for 7th chords can be pressed along with any of the previously described 12 chords to produce another 12 7th chords.The minor and 7th buttons can be pushed down together to produce another 12 chords. Therefore, with 9 buttons one can achieve 48 different chords. Other buttons such an 1th button or any number of other buttons could be added. With a minor, 4th, 7th and I 1th button, the user can achieve 96 chords with a combination of no more than 4 of 11 buttons (maximum 2 buttons for sharp or flat chord + I button for minor + 1 button for 4th 7th 1th variation = 4 buttons) as

shown in Table 2.

Alternatively, configuration of 48 different chords as described above can also be achieved by programming the buttons such that the first button pressed down is the root of the chord. If another button in the same row is pushed, it represents the sharp or flat of that chord. The buttons of the row which was not the row on which the first button is pushed changes and it becomes the buttons for minor, 7th and I 1th* So, in this configuration 48 chords are accessible through 7 buttons. There are a large number of combinations and variations of the above.

As well as representing chords, the buttons 80 can also represent notes when the software is put into a different mode. The buttons 80 are labelled with the number 1-7, which represent the number of the fret against which the string on a traditional guitar would be stopped. For example, when button 80b is pushed and a string is plucked, invention will make the sound for the plucked string stopped at the second fret. Figure 23 shows the equivalent finger positions on a traditional guitar for the sounds that would be played by pressing the 2' button in note mode on the guitar invention. A disadvantage of this configuration is that only one fret number can be played for all strings at any one time, i.e., you cannot play fret two of string I and fret 3 of string 2 at the same time.

Whilst the present invention has been described with numerous examples and alternatives, there are a number of additional modifications that may be offered and which offer numerous additional advantages. For example, each row of buttons 80 may have a different texture in order to give a tactile clue to hand/finger position or each row of buttons 80 may be at a different height in order to give a tactile clue to hand/finger position. Alternatively, each individual button may have a Braille type of embossing in order to give a tactile clue as to exact finger position. Each button or at least top row of buttons may have its type (C, D or E) printed on its top-side in order that the musician may be able to see the note without having to peer over the front face of the guitar to confirm the finger and button position.

It will be appreciated that the present invention provides a number of options to that of the traditional string instrument. In essence, the invention provides a series of switches/sensors as described and a method of arranging/using them that allows tactile feedback such that the buttons/switches can be recognised and distinguished from each through the feeling sensation of the users fingers rather than by any visual cue. The switches/sensors may be of various shapes or have various textures and may be caused to vibrate by the action of the controller should that prove useful. Alternatively, the switches/buttons may be lit and distinguished by means of light or a visual cue controlled by the controller. It will also be appreciated that the switches/sensors may be moved to other positions in respect to the strings without altering the function thereof. The switches/sensors are conveniently placed on the neck of an instrument whilst the string portion is placed on the body.

Note Same as:

IC

2 C# ("C sharp") Db(D flat)" 3D 4 D# ("D sharp") Eb ("E flat") 5E 6F 7 F# ("F sharp") G" ("G flat") 8G 9 G# ("G Ab ("A flat") sharp")

A

11 A# ("A sharp") B' ("B flat") 12 B

Table I

Major Minor Regular chords 12 12 4thvariation 12 12 7th variation 12 12 11tvariation 12 12 Subtotal 48 48 Total chords 96

Table 2

Claims

Claims: 1 A string assembly for a musical instrument having: a string,

having a first and a second portion; a string deflection sensor for sensing deflection of the string; characterised by: a string mounting member for mounting said first portion for lateral motion upon being struck by a player.

2. A string assembly as claimed in claim 1 wherein said playing portion and sensing portion are joined to each other by a joint such that lateral displacement of the playing portion causes displacement of the sensing portion.

3. A string assembly as claimed in claim 1 or claim 2 wherein the sensor is mounted for detecting motion of the second portion.

4. A string assembly as claimed in claim 1 or claim 2 wherein the sensor is mounted for detecting motion of the first portion.

5. A string assembly as claimed in any one of claims 1 to 4 wherein the string mounting member is a spring assembly.

6. A string assembly as claimed in claim 5 wherein the spring assembly includes a tensioning member for applying a tension to said string.

7. A string assembly as claimed in any one of claims 1 to 6 wherein the first portion comprises a relatively rigid playing portion and the second portion comprises a relatively flexible portion.

8. A string assembly as claimed in any one of claims I to 6 wherein the first and second portions comprise relatively rigid portions.

9. A string assembly as claimed in any one of claims I to 7 wherein the second portion comprises an electrically conductive portion forming part of an electrical circuit which, upon displacement of the first portion contacts the string deflection sensor and completes an electrical circuit.

10. A string assembly as claimed in claim 8 wherein the string deflection sensor includes a plurality of deflection sensors laterally and axially displaced along the second portion such that the greater the lateral displacement of the string the greater the number of sensors that come into contact with said second io portion.

11. A string assembly as claimed in any one of claims I to 7 wherein the first portion includes an electrically conductive portion forming part of an electrical circuit which, upon displacement of the first portion contacts the string deflection sensor and completes an electrical circuit.

12. A string assembly as claimed in any one of claims I to 11 and including a string motion damper.

13. A string assembly as claimed in claim 11 in which the motion damper comprises a tube in frictional contact with and surrounding a spring connected to said first portion of said string.

14. A string assembly as claimed in any one of claims 1 to 13 and including a plurality of said strings and sensors.

15. A string assembly as claimed in any one of claims Ito 14 including a chassis member onto which said string assembly is mounted.

16. A musical instrument comprising a string assembly as claimed in any one of claims Ito 15.

17. A finger button arrangement of electrical switches for an electronic musical instrument in which said finger buttons correspond to notes on a scale wherein: said buttons are arranged in two groups, one group containing the buttons for notes C,D and E and the other group containing the buttons for notes F,G,A and B and in which a flat or a sharp note of a scale is represented by actuation of two buttons in any one group 18. A finger button arrangement as claimed in claim 17 wherein the buttons are arranged in scale note order.

19. A finger button arrangement as claimed in claim 17 or claim 18 including an interface for detecting simultaneous depression of two adjacent buttons and for causing the creation of a signal for playing a sharp or a flat note corresponding to the note associated with the depressed buttons.

20. A finger button arrangement as claimed in any one of claims 17 to 19 wherein one or more of said buttons are individually programmable.

21. A finger button arrangement as claimed in any one of claims 17 to 20 wherein the button arrangement forms part of a group of buttons arranged in parallel rows.

22. A finger button arrangement as claimed in claim 21 wherein a button outside of said two groups is programmable to perform a user defined function.

23. A finger button arrangement as claimed in any one of claims 17 to 22 including a chord modifying button.

24. A control button assembly comprising a plurality of buttons, each of which is operable to modify the output of all the finger buttons of any one of claims 17 to 23.

25. A control button assembly comprising three switches arranged such that, a first of said switches is operable with said second or said third and said second and third are not operable together.

26. A control button assembly as claimed in claim 24 or claim 25 including a shield for shielding two of said buttons and for guiding a digit of an operator in the direction of one or other but not both of said shielded buttons.

27. A control button assembly as claimed in claim 26 including a mechanical or io electrical interlock preventing a operation of two of said buttons together.

28. A finger button arrangement as claimed in any one of claims 1 to 7 including a control button assembly as claimed in any one of claims 24 to 27.

29. A finger button arrangement as claimed in any one of claim 17 to 28 wherein the control button assembly comprises a chord selection button assembly.

30. A finger button arrangement as claimed in claim 29 wherein the first button comprises a button for the selection of a minor chord.

31. A finger button arrangement as claimed in claim 30 wherein the second and the third buttons comprise buttons for the selection of a chord.

32. A musical instrument having a finger button arrangement as claimed in any oneofclaimsl7to3l.

33. A musical instrument as claimed in claim 32 and having a plurality of said control button assemblies for the selection of a plurality of chords.

34. A musical instrument as claimed in either of claims 32 or 33 and comprising a stringed instrument.

35. A musical instrument as claimed in any one of claims 17 to 34 and including a signal processing means for processing signals received from said electrical switches of claims 17 to 23 or said buttons of claims 24 to 26 and sound generating means for receiving said signals and for generating sounds in accordance with said received signals.

36. A musical instrument as claimed in any one of claims 17 to 35 and including signal processing means for receiving signals from two of said electrical switches and causing the generation of a note corresponding to the sharp or the flat of the note associated with depression of said buttons.

37. A method of operating a stringed musical instrument according to any one of claims I to 36 having the steps of: detecting deflection of one or more of a plurality of strings; passing data relating to the deflection to a control device; and instructing an audio device to play a sound allocated to said string.

38. A method as claimed in claim 37 including the step of responding according to whether the string has been either plucked or hit and if plucked delaying the generation of sound until the string has been released.

39. A method as claimed in claim 37 or claim 38 and further including the step of detecting the magnitude of deflection of the string and increasing the volume of the sound generated in accordance with a predetermined relationship between the magnitude of deflection and the volume of the sound generated.

40. A method as claimed in any one of claims 37 to 39 including the step of detecting when a previously deflected string is deflected again and stopping the generation of the earlier generated sound and generating a new sound according to the data generated as a result of the second or subsequent deflection of said string.

41. A method as claimed in any one of claims 37 to 40 including the step of modifying the sound generated as a result of a string being plucked or hit upon receipt of a signal form one or more operator actuated switches.

42. A method as claimed in claim 41 including the step of altering the note or chord played upon receipt of a signal from the one or more operator actuated switches.

43. A method as claimed in any one of claims 37 to 42 including the step of generating the sound from a sound apparatus external to the musical instrument.

44. A method as claimed in any one of claims 37 to 43 when performed by a computer programmed to perform the method.

45. A computer when programmed to perform the method as claimed in any one of claims 37 to 44.