GB2426118A - A brace for a musical instrument - Google Patents

Abstract

A brace for a musical instrument and a bracing system for a musical instrument wherein the brace(s) contain recesses to give them greater flexibility and to produce novel tones from the instrument. The recesses also allow for overlapping braces to avoid touching each other.

Description

I

A BRACE FOR A MUSICAL INSTRUMENT

The present invention relates to improvements in a brace and is particularly applicable but in no way limited to a brace for a musical instrument, especially a guitar.

A typical acoustic guitar has a hollow body connected to a neck. The hollow body has a soundboard with a soundhole, a backboard spaced from the soundboard and sidewalls defining a soundbox.

The acoustic guitar has a series of strings strung at substantial tension from a bridge on the soundboard, across the soundhole and along the neck. The string tension creates forces which act on the soundboard and which, over time, can cause bending, cracking or other damage to the soundboard. This can result in structurat failure and/or altered acoustic properties.

The soundboard must be capable of sufficient vibration to create a suitable noise but must also be rigid enough to withstand the forces acting on the soundboard from the string tension. These requirements are at crossed-purposes and it has proved difficult to create an acoustic guitar that excels at both of these properties.

Generally, a thinner soundboard is desirable but in order to withstand the tension from the strings, bracing must be provided on the soundboard. Up to now it has proved difficult to create bracing that provided sufficient strength without impairing the sound quality and volume. Indeed the numerous bracing designs testify the great difficulty in achieving these objectives.

Accordingly there is provided according to a first aspect of the present invention a brace for the soundboard of a musical instrument wherein the brace incorporates recesses.

For the first time, there is provided a brace for use with a musical instrument that incorporates recesses. The term brace is intended to include all forms of support attached to the inside of a musical instrument and the term brace is intended to be equivalent with the term strut or any other form of support for a soundboard. The braces or struts prevent tension from the strings or other parts of the instrument from adversely affecting the soundboard. The brace is generally attached to the underside of the soundboard but could equally find use in some other region in the soundbox, including the sidewalls or bottom wall.

The term recess is intended to be interpreted broadly and generally means a hole through the brace, from one side to the other. In one embodiment, the recess is defined by an archway, of any shape, through the brace giving a passageway from one side of the brace to the other.

The recess could be considered to be a cutaway from the brace although the term cutaway does not necessarily signify that a portion of the brace has been physically cut out. It would also include a brace formed with the cutaway already included.

Essentially the recess allows passage from one side of the recess to the other. The brace can take a number of shapes but is generafly attached to the soundboard on one face, the bottom face, with a top face facing away from the soundboard. There are two side faces and two end faces. The recess allows passageway through the brace from one side face to the other side face.

The brace improves the instrument in many unexpected and surprising ways.

Firstly, the recesses improve the volume of the instrument, that is, the sound from the strings is amplified by the soundboard and soundbox by a greater degree. It is believed that this could be caused by a number of reasons, either individually or in combination. The recesses improve the flexibility of the brace. This allows the soundboard to vibrate to a greater extent and therefore amplify the strings more strongly. The increased vibration affects the air in the soundbox and results in a greater volume from the instrument.

It is also believed that the soundwaves, travelling through the soundboard and/or the soundwaves travelling through the air within the soundbox are more able to move through the braces thereby increasing the volume of air that can move within the soundbox, increasing the volume of the sound.

One of the advantages of the present invention is that, in contrast with bracing designs of the prior art, the sound can easily move through the bracing. Previously, when the soundwaves were faced with a brace that was to some degree orthogonal to the direction of the wave, the brace had a side facing the oncoming wave and this face reflected the sounds back, making it difficult for the soundwaves to escape through the soundhole. In contrast, for the first time, there is provided recesses to allow the soundwaves to pass through the braces so that they do not adversely affect the sound that is produced.

The term soundwave includes either the waves that are travelling over and through the soundboard, the soundwaves formed in the air within the soundbox or a combination of the two. The present invention improves the transmitting quality of one or both of the above types of waves.

Another surprising advantage found by the recesses is that the braces can be made more flexible. This allows the instrument designer to use more braces than they would normally consider because the increased flexibility ensures that the soundboard can still vibrate to a sufficient degree to create the desired sound.

Braces have several uses within the soundbox. As well as providing the necessary support for the soundboard, they also increase the stiffness of the soundboard.

While it could be perceived that a soundboard which is as flexible as possible would be desired, this often leads to the loss of the treble and mid-tones of the instrument and also affects the ability to play notes rapidly, the so called transient tone, because the oscillations generated from playing one note are not dampened quickly enough before the next note is played, leading to a muddled sound.

Furthermore, the braces allow the sound to travel from the strings, via the bridge, to the distant parts of the soundboard. The vibrations can travel from the bridge along the braces to help distant parts of the soundboard vibrate. It is believed that the braces allow the waves to travel along them but to some degree reflect waves that try to pass over them. That is a wave travelling along the brace in a longitudinal direction will travel but a wave travelling in a across the brace in an orthogonal direction may be resisted or reflected.

The braces can also help define areas of the soundboard for specific types of vibrations. Braces placed close together will prevent large amplitude oscillations that create bass tones, but enhance small amplitude vibrations, creating treble tones.

By having the correct amount of braces, positioned accurately allows for a balanced sound with the desired amount of bass, mid-tones and treble. The problem to date has been that to position the braces in such a position resulted in the overall vibrations being stifled, creating an instrument that was too quiet. Specifically, the bass tones were generally not loud enough.

For the first time, it is possible to arrange the braces in arrangements that were never considered viable because of the increased flexibility of the braces.

Furthermore, very strong strut arrangements can be considered which gives rise to the possibility of a very thin soundboard. This has not been possible before, without compromising on the sound and/or the volume.

A further advantage of the recesses is that there are a number of regions introduced into the soundbox that can affect the soundwaves that are being formed within it.

When the soundwaves enter the recess they are amplified as they leave the other side. The effect is similar to waves entering a slit and being amplified on the other side. When the waves pass through the recess, it is believed that the waves spread out like ripples on a pond. When the ripples from one recess meet the ripples from another recess they can interact, either amplifying or cancelling each other to varying degrees at different wavelengths. Having several recesses in the same area introduces the possibility of overlapping the waves to produce interesting and new harmonics, brilliance and sustain. This creates new and unusual sounds that have not been heard from instruments before.

The present invention also advantageously affects the sound in other ways. For example, the sound itself is very different in the musical instrument in' that for a given note that is played, various "harmonic" sounds can also be heard. This creates a very interesting sound in that when playing one note, various other complementary harmonic notes can also be heard at the same time. This has a very beneficial effect on the sound of the instrument.

The brace also affects the sustain of the note. It has been noticed that the sustain is very good in that the sustain plateaux's instead of dying away. In a normal instrument when the string is plucked the noise produced initially increases and then fades away. In the present invention, however, the noise increases and then plateaux's and stays at a given volume for longer before dying away. This gives an interesting sound to the instrument. The sustain is especially noticeable on the mid- range and treble which is ideal for a classical guitar. There is a perception that the volume of the note actually increases before fading away.

The brace also affects the brilliance of the instrument, especially the mid-range and treble.

The brace can drastically improve the strength of the guitar and therefore its longevity. It is believed that a guitar with a thin soundboard made according to the current invention should last considerably longer than previous designs.

Yet another advantage of the present invention is that by specific placement of the recesses on the braces, overlapping braces can be designed so that they do not touch. This allows the designer far more freedom in arranging the braces and means that braces can be very strong in one direction while being far more flexible in another. Up to now, the brace arrangement has been of a uniform strength, which has limited possible designs because the braces have all been rigidly attached to each other when they intersect Preferably the recesses can be adjusted to change the sound produced by the instrument. This could be while the instrument is being made or even once it has been finished. By adjusting the position, shape and size of the recesses and/or braces it is now possible to dramatically alter the sound produced by the instrument in relation to any combination of its transient tones, harmonics, sustain and/or brilliance. The vastly increased flexibility in the options available to the designer mean that instruments can be tailor made to the particular needs. If it is decided that the sound should be changed, it is not difficult to adjust the recesses, or replace the braces entirely with a different arrangement (braces are generally glued into position with a reversible glue).

It is also possible to design the recesses such that they can be adjusted in situ. This could take the form of an arrangement in which their size can be adjusted. If this system is employed it is important to ensure that the mechanism does not introduce unwanted rattles into the soundhole.

According to a preferred embodiment, the recesses comprise substantially semicircular archways through the brace. If the recess is formed in the bottom of the brace, that is the portion of the brace attached to the sound board, then the area removed from the brace is in the shape of a semicircle, the sound board forming a line bisecting the imaginary circle. In essence though, any shape can be employed and all are included in the present invention. It should be appreciated that different shapes may affect the tone produced by the instrument. Other shapes can and are considered including, circles, ovals, squares or slots. It should be realised that the definitions of the shapes are only intended as guide and a shape that is similar would also fall within a particular definition.

Preferably, the brace contains between 1 and 20 recesses. More preferably, the brace contains between 2 and 15 recesses and even more preferably, the brace contains between 3 and 10 recesses. The number of recesses chosen will depend upon the type of sound that is desired, taking into account the amplification effects, the flexibility effects and the arrangement of braces that is desired.

When the braces are been attached to a soundboard during construction, the soundboard is turned upside-down. Once the instrument has been completed the soundboard is considered the front of the instrument. Therefore the orientation of the soundboard and consequently the braces will change as the guitar is made. For the purposes of the present invention, the terms "bottom" and "top" refer to the soundboard when it is being made, that is turned around with the braces visible.

In one embodiment, the recesses are formed in the bottom portion of the brace to be connected to the soundboard. That is when the brace is connected to the soundboard, one of its faces will abut the soundboard. In this instance the recesses, possibly in the form of semicircular archways, will also abut the soundboard. If the brace is considered a bridge, the soundboard would be the water and the recesses would be the archways in the bridge to allow the water and air to flow through. This analogy is useful in that it gives an idea of how the soundwaves are affected when they travel through the recess or archway.

Equafly, the recesses could be formed in the top portion of the brace not connected to the soundboard. This is the opposite side of the brace to that described above and can be thought of as an upside down bridge.

In a particularly preferred embodiment the recesses are formed in both the bottom portion of the brace connected to the soundboard and the top portion of the brace not connected to the soundboard. This gives the brace increased flexibility. It is perfectly possible for a bracing system to include any combination of braces with recesses in the bottom, braces with recesses in the top and braces with recesses in both the bottom and the top.

A particular advantage with the recess system is that when two braces overlap, at the position where they overlap a recess in the top portion of a first brace and a recess in the bottom portion of a second brace coincide, such that the two braces do not touch each other. The size and shape of the recesses can be configured such that the gap between the overlapping braces is either smaller or alternatively larger.

This system means that the overlapping braces can vibrate independently of each other and the vibrations in one direction are not stifled by a brace travelling in the other direction. In essence, overlapping braces are not fixed to each other, hindering the ability for waves to travel through the braces and for waves to travel across and on the soundboard itself.

When the soundboard is vibrating, overlapping braces may vibrate with different frequencies and/or amplitudes. For example, the more rigid longitudinal braces that are necessary to support the tension from the strings may not vibrate as much as orthogonal braces which can be used to help transmit these waves across the soundboard. In the present invention, this orthogonal movement is not hindered by the more rigid longitudinal bracing. Therefore, for the first time, it is possible to ensure that each brace in the bracing system is able to be designed to have the optimum properties with regard to its strength and its ability to vibrate.

It is preferable that the recesses in the overlapping region are configured such that the braces do not touch each other even when given the vibration that they are likely to be subjected to. This will obviously vary with the specific bracing arrangements.

It is perfectly possible for a given brace to overlap in more than one position with more than one brace and it is envisaged that there may be a plurality of braces all overlapping with each other, with at least some but more preferably all of these braces configured not to touch each other where they overlap.

In a configuration which comprises a number of braces, it is preferable that the recesses in the braces are aligned. For example, if the bracing system comprises a number of orthogonal braces, it is desirable that the recesses in each brace are aligned such that looking along the soundboard the recesses are lined up with each other. The advantage of this is that there is an easy passageway for the soundwaves to travel along the soundboard and through the bracing system. It ensures that the soundwaves can travel up the soundboard to the sound hole without being presented with a surface in which they cannot easily pass through.

This helps to increase the volume of the sound that is produced. This may also help to create specific harmonic responses because the aligned recesses can set up specific wave patterns within the bracing system.

The recess is defined by an inner surface in the brace and preferably the brace further comprises a member adapted to connect to said inner surface and extend beyond the width of the brace. The member could be made from any material and the choice of material may affect the sound that is produced. In one preferred embodiment, the material is selected from a thin piece of wood or carbon. This member is placed in the recess, attached to the inner surface of the recess. Part of the member extends out from the recess, either on one or both sides. This has the effect of channelling the soundwaves travelling through the recess and can affect the volume and/or the sound that is produced. The member may be shaped into a funnel or other arrangement in order to affect how the soundwaves travel through the brace. Indeed, any way to shape the recess either by adjusting its shape or adding other members to it in order to adjust the properties of the waves travelling through are included within the scope of the present invention. The member be placed in any or all of the recesses, including the recesses longitudinal and/or orthogonal braces. The member may be placed in only certain recesses on a brace or alternatively all available recesses in the system.

According to a particularly preferred embodiment1 the braces include harmonic bars and the harmonic bars contain recesses. The harmonic bars are generally found either below, above or both below and above the sound hole. By putting recesses in the harmonic bars, the soundwaves are allowed to travel through the bar and out of the sound hole. This helps to improve the sound that is produced in terms of volume and/or tone. By placing recesses in a harmonic bar above the sound hole, any soundwaves and notes or tones produced by the soundboard above the sound hole can also escape out of the sound hole more easily.

Preferably, the recesses in the harmonic bars are aligned with at least some of the recesses in the rest of the bracing. This alignment allows for the sound to more easily leave the sound hole.

According to a particularly preferred embodiment, the bracing comprises longitudinally aligned and orthogonally aligned braces with respect to the body of the instrument. The longitudinally aligned braces generally provide support for the tension in the strings and the orthogonally aligned braces allow the soundwaves to travel transversely across the soundboard. This arrangement is particularly preferred because it provides the most support for the soundboard with respect to the string tension but also allows the soundwaves to travel easily across the surface of the soundboard.

Preferably, the orthogonal braces are more flexible than the longitudinal braces.

* This ensures that the longitudinal bracing that is most required to strengthen the soundboard is stronger and that the orthogonal bracing that is most required to help transmit the soundwaves is more adapted to do so. One preferably way to achieve this is to make the orthogonal braces comprise more recesses than the longitudinal braces. This measure ensures that the orthogonal braces are more flexible because they comprise more recesses which mean that there is less material attached to the soundboard and there is generally less material in the brace to give it rigidity.

According to an alternative embodiment of the present invention, the braces are not aligned longitudinally and orthogonally. Instead, the braces are placed at an angle to the longitudinal line of the guitar. Preferably an angle range of 15-75 degrees is used, more preferably 25-65, even more preferably 35 to 55 and particularly preferably 40 to 50 degrees. An especially preferred angle is 45 degrees or therea bouts.

With this angled grid, the struts do not provide as much support to counter the tension from the strings. To overcome this, it is possible to use a frame inside the soundbox, which is directly connected to the neck to take this strain. The frame can run around the edge of the soundboard and prevents the tension from the strings being directed to the soundboard. Thus, the struts do not need to take as large a strain and consequently do not need to be aligned with the strings. This gives rise to further design possibilities where the struts major function is not support but is more for the sound changes they make to the soundboard.

The frame need not be attached to the soundboard and a gap can be maintained between the soundboard and the frame to further improve the sound qualities.

It is also not necessary to have a central soundhole, this can be replaced by differently positioned soundholes (preferably at either side of the frame near the neck). This removes the need for harmonic bars around the soundhole which improves the sound quality since this region is free to vibrate and contribute to the sound and the bars and soundhole do not form a barrier to prevent the sound travelling up and down the length of the soundboard.

Preferably, the braces comprise scalloped ends. This has a number of advantages in that it allows the edge of the soundboard to vibrate more freely because there is less bracing present. This provides an area for base tones to be generated because the soundboard is able to vibrate more. By scalloping the ends, it can be thought of as a taper, it also ensures that there is no point on the soundboard which goes from maximum braced strength to no bracing at all. These points adversely affect the quality of sound and also create stress points in the soundboard. Indeed, not tapering the ends could lead to the soundboard lifting away at this point.

According to a particularly preferred embodiment, the braces are arranged in a grid arrangement. It is believed that this grid arrangement, which could be considered a crisscross grid pattern, is the best arrangement for providing an even response.

This may be because the energy emanating from the bridge extends in a radial fashion. This gives rise to a tendency for nodal areas to appear as radii from the bridge location. By using non-radial bracing, the ultimate example being the grid arrangement, it prevents the formation of nodal patterns of corresponding frequencies. This ensures that the situation is avoided where the soundboard has points where the frequencies are amplified and points where the frequencies are substantially cancelled. Therefore, the effects of unequal note volume are evened out with this bracing pattern. Prior to the present invention, grid arrangements have not been possible, or effective, because of the reduction in the ability of the soundboard to vibrate. Prior to the present invention, a grid system would produce a too quiet tone because the soundboard could not vibrate properly due to the substantial bracing. The instrument was therefore too quiet and ineffective. For the first time, using a brace according to the present invention, a grid arrangement can be used which provides all the advantages of a grid system but nevertheless allows the soundboard to vibrate sufficiently to produce a desirable sound that is loud enough.

Preferably, the grid is aligned longitudinally and orthogonally with respect to the body of the instrument. This ensures that the longitudinal braces can fully support the tension from the strings and this longitudinal and orthogonal arrangement is preferred to give the best response.

In an alternative arrangement the grid is not angled longitudinally and orthogonally with respect to the body of the instrument and is offset. This is used when the grid does not need to support a high tension from the strings, either from low tension strings or from the use of a frame or other arrangement to remove the tension from the soundboard. In this arrangement all braces can be of the same, or different, strength and flexibility.

Preferably, the grid is substantially symmetrical about the longitudinal axis of the instrument. It had been believed that by providing nonsymmetrical bracing systems helped the instrument to produce sounds across a whole frequency range. If the bracing was arranged such that there was more space between braces on the side of the instrument which contained the lower strings but less space between braces on the side of the instrument which contained the higher strings, it was believed that each string was provided with an area in which It could create the correct vibrations on the soundboard to improve the sound produced by that particular string. It has been discovered by the present invention that this is not necessary and that the grid arrangement allows for production of soundwaves across all frequencies without the need for a non-symmetrical grid arrangement. Advantageously, this means that the soundboard can be fully supported across its entire surface with no weak points.

Indeed, using a grid arrangement means that the soundboard can be made very strong. This means that a much thinner soundboard can be used, increasing the performance of the instrument. Alternatively, or in addition, it also means that the life expectancy of the instrument can be dramatically increased.

In a preferred embodiment, the braces define a series of regions and each region has at least one recess leading into it. The soundboard can then be thought of as being split into a series of regions, each region being defined by the braces surrounding it. This gives rise to the possibility that different defined regions on the soundboard can be essentially separated from each other, giving rise to different frequency responses in each region. This allows the designer far greater scope to adjust the response of a given instrument.

By ensuring that each region has at least one recess leading into it, the soundwaves can easily move into and between the different regions. In a particularly preferred embodiment each region has more than one recess leading into it. This could be two, three, four or more recesses leading into and out of each region. This gives rise to the possibility for the soundwaves to travel into each region from more than one area, giving rise to the possibility of interference patterns being set up in each region. Essentially, depending on where the soundwaves have come from, each region may have a different interference pattern within it. Allows for different tones, and types of responses in each region. By placing several regions together, the soundwaves can travel through each region giving rise to interesting interference patterns and consequently interesting changes to the notes. These changes can include changes to the sustain of the note, changes to the brilliance of the note, and also changes to the harmonics that are heard with each note. This arrangement may also give rise to other advantageous properties.

Where the bracing system is a grid system, there is essentially provided a series of rectangular or square regions together. By ensuring that each side of each region has a recess within the brace, each region is connected to the others via a series of interconnected recesses. It is believed that the soundwaves can move easily through this system, and alsoare changed as they travel through the bracing system, which gives rise to the interesting tonal response of the instrument.

Preferably, each side of each region is defined by a brace containing a recess. An area on the soundboard may also be defined a region if it is substantially enclosed by braces. For example at the edges of a grid system arrangement, there are areas which are only enclosed on two or three sides. These allow for greater vibrations in the area, giving rise to improved base response but because they also contain recesses into them, they should be considered regions.

The height of the braces can vary according to the individual instrument. In addition, the braces may taper inwards, giving a wider base attached to the soundboard and a narrower top distant from the soundboard. Generally, braces are less than 3 cm high, and often less than 2 cm high. The actual height will vary depending on the type of brace that is required, and also the position of the brace on the soundboard.

Therefore it is conceivable that different braces within a bracing system are of different heights. The braces may be uniform in height over their length or may alternatively be shaped such that they taper down at their ends or indeed are curved, with their highest point in the middle. Whilst the braces do not generally extend substantially into the soundbox given that the overall width of the soundbox is considerably more than the height of the braces, the braces have a substantial effect on the sound that is produced, either by their effect on the vibrations of the soundboard, the effect of the waves travelling through the soundboard at the point of the recesses, or the effect of the air travelling through the recesses in the soundbox.

These effects individually, or in any combination, affect the sound that is produced from the instrument.

It is also possible for the struts to extend much further into the soundbox. This is not necessary to increase the strength of the soundboard but will have a material effect on the sound that is produced. By providing enough recesses, holes or archways in the extended braces, the sound produced can still be loud enough but is affected by said recesses. These extensions could also be considered baffles within the soundbox. Equally, the baffles could be placed on different surfaces within the soundbox, for example the sidewafis or back wall.

The present invention also covers a soundboard attached to a brace as described above. This includes any type of soundboard incorporating one or more braces as defined in the present invention. Preferably, the soundboard further comprises a groove or grooves. Particularly preferably, the groove(s) run(s) around at least a portion of the perimeter of the soundboard. This has the advantage that when waves travel towards the edge of the soundboard and approach the sidewalls, they are reflected back and/or up so that the sound is not dissipated by the sidewall. The groove in the soundboard is essentially a trough or dip in the soundboard, resembling a shallow trench. It is generally not particularly deep and its depth will depend on the thickness of the soundboard itself.

In a preferred embodiment, the groove(s) extends through one or more of the recesses. These grooves help channel the sound through the recesses and help to evenly distribute the sound produced by the soundboard. By introducing these grooves the soundwaves have channels to run up and also the grooves increase the reflections within the recesses and also the regions defined by the braces. This has a material way in which the soundwaves are reflected within the regions. In a particularly preferred embodiment, the groove(s) extends longitudinally up the soundboard. This helps the sound travel up the soundboard and out of the sound hole.

Alternatively, or in addition to the grooves, a frame can be used to support the tension from the strings. This frame may extend around the soundboard, in the same region as the groove. The frame can either be attached to the soundboard, attached in places or independent of the soundboard. It is generally made separately from the soundboard. The frame may be attached to the neck and runs direct from the neck/body joint. By using a frame the stress exerted on the soundboard is reduced. When using a frame, a soundhole in the centre of the soundboard is generally not preferred and is not included. Therefore, an advantage of using the frame is that the soundboard does not require harmonic bars to support the soundhole. The original soundhole and harmonic bars cause stress to that part of the guitar, which in turn causes loss of energy from the soundboard. This energy loss is between the soundhole and the bridge, and because of this soundhole positioning, this area of the soundboard is weakened. It is also believed that this stops a lot of sound frequency transferal from the nodal ends i.e. string ends nutlsaddle where the strings start and finish. This is important for the transferal of sound frequencies to be able to travel from one end of the string down the neck of the guitar into the soundboard, as it is from the other end of the string into the saddle/bridge. With a soundhole, sound cannot travel through this soundhole instead it dissipates into each side of the guitar around the soundhole and into the sides and back of the guitar. This unfortunate characteristic is a feature of guitar construction today.

The frame may connects directly from the neck/fingerboard of the guitar directly to the soundboard area. A purpose of the frame is to take the stresses from the string tension so that they are not transmitted to the soundboard. The forces are absorbed by the frame, which means that they are not transmitted to the soundboard. This means that the bracing system on the frame do not need counter the forces from the strings. The bracing system instead is used to take the strain from the bridge and to transmit the souridwaves across the soundboard in the desired manner. In essence, the frame provides the strength and the bracing system provides the desired sound effects.

The frame itself can take any shape. Preferably, an A shape or tennis racquet shape can be used. Some preferred but not essential dimensions are a substantially half inch lip around the outer edge exactly like a drum rim. The width of the frame on the underside can be approx. one and a quarter inches wide. This may preferably be routed out to a depth of approx. three eighths of an inch. This can preferably create a gap between the underside of the soundboard and frame.

This has an advantage in that the frequencies can bounce back and forth from the soundboard to give a good sustained sound. As stated above, the frame also takes the forces from the string tension leaving the bracing system to be designed and positioned to create the optimum sound effects.

In one embodiment, the soundboard is domed. This increases the strength of the soundboard and therefore the instrument itself. However, it is also possible for the soundboard to be flat. By doming the soundboard the soundwaves are reflected differently off of the soundboard which changes the sound produced by the instrument. It is possible for the designer to specifically select a degree of doming or alternatively choose a flat soundboard depending on the requirements that they specifically have. In addition to this, the back board can either be domed or flat for the same reasons.

The thickness of the soundboard can be adjusted to suit the individual needs of the instrument. For example, a thinner soundboard increases the vibrations on the instrument, which is generally more desirable. However, because the soundboard itself is thinner, it is far more susceptible to warpage and damage and therefore the instrument will be more prone to accidents and also will deform over time. It is the braces that help prevent this from happening. Because of the brace as defined above, the soundboard according to a preferred embodiment of the invention is less than 3 mm thick. More preferably, the soundboard is less than 2 mm thick and even more preferably the soundboard is less than 1.8 mm thick or even less than 1.5mm thick. For the first time it is possible to create a musical instrument with a very thin soundboard. Up to date, soundboards that are this thin would either buckle under the string tension or alternatively be made too rigid by the necessary amount of bracing to strengthen it. For the first time, according to the present invention, there is provided bracing that allows for a very strong soundboard without adversely affecting the sound it produces.

According to a particularly preferred embodiment, the musical instrument is a guitar.

Even more preferably, this could take the form of either a steel stringed guitar or a classical guitar.

Alternatively, the musical instrument is selected from the group consisting of a violin, viola, cello, double bass, acoustic bass, or jazz guitar. Indeed, a brace according to the present Invention can advantageously be used in any stringed instrument, but is more particularly suited to instruments which require a bracing system or have a large soundboard.

According to a second embodiment of the present invention, there is provided a bracing arrangement for the soundboard of a musical instrument wherein at least some of the braces overlap each other characterised in that the braces are configured not to touch each other in the overlapping region. For the first time there is provided a musical instrument in which overlapping braces are designed not to touch each other. This allows for many advantages over the prior art in that the braces can move independently of each other, are not tied together, thus inhibiting the vibration of a given brace and it also allows for strong longitudinal braces and more flexible orthogonal or other braces. This can be achieved in numerous ways, all of which are encompassed by the present invention. In a preferred embodiment, however, there is provided a bracing arrangement as set out above. This is equally applicable to a bracing system where the grid is not aligned with the strings.

According to a third embodiment of the present invention, there is provided a bracing arrangement for the soundboard of a musical instrument wherein the braces comprise longitudinally aligned and orthogonally aligned braces with respect to the body of the instrument characterised in that the orthogonal braces are more flexible than the longitudinal braces. This arrangement has not been seen before and allows for the longitudinal braces to support the tension from the strings and the orthogonal braces to ensure that an even response is found from the instrument.

Again, this may be achieved by the bracing system defined above but not limited to such an arrangement.

The present invention also includes a musical instrument comprising at least one brace according to any preceding claim. More preferably, the present invention covers a guitar comprising at least one brace according to any preceding claim.

The invention will now be further described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a typical guitar; Figure 2 shows various bracing configurations; Figure 3 shows a perspective view of the undersign of a soundboard which has a bracing arrangement attached to it; Figure 4 shows top and side views of the soundboard; Figure 5 shows a perspective view of a bracing arrangement; Figure 6 shows top and side views of a bracing configuration; Figure 7 shows side views of braces according to the present invention; Figure 8 shows pictures of some of the stages of construction of a musical instrument; Figure 9 shows a perspective view of the underside of a soundboard according to a further embodiment of the present invention which has a bracing arrangement attached to it; Figure 10 shows a frame attached to the neck of a guitar, the frame used to support the tension of the strings; Figure 11 shows a guitar with the frame and the soundboard in position; Figure 12 shows a backboard, which further comprises bracing according to the present invention; Figure 13 shows a near completed guitar according to an aspect of the present invention.

Embodiments of the present invention are described below by way of example only.

These examples represent the best ways of putting the invention into practice that are currently known to the Applicant, although they are not the only ways in which this could be achieved.

Figure 1 shows an acoustic guitar 10 having a hollow body 11 and a neck 12. The body has a soundboard 13 with a circular soundhole 14. The soundboard 13 is connected to a sidewall 15 which, in turn, is connected to a backboard 16. The neck 12 has a headstock 17, and strings (not shown) are strung from the headstock 17 in a direction along the neck 12, across the soundhote 14 and to a bridge (not shown) on the soundboard 13.

The soundboard is the primary sound producing member. The sides and back form a resonant sound-reinforcing chamber. The soundboard is typically made of wood as are the sidewalls and back wall on traditional instruments. The back is generally arched to assist audio reflection, smooth frequency response, and to provide a desired degree of reverberation. The sides of an acoustic guitar are often of the same construction as that of the back, though laminations of hardwood veneers can also be used. Traditionally, necks have been carved from one block of wood. Since this requires a large piece of wood and great waste, necks are generally built up from several pieces. Due to consideration of warping and unequal string tension, the lengthwise laminated neck has achieved increased popularity. The most common materials for necks are mahogany and maple. Mahogany possesses a high degree of dimensional stability, but its flexibility absorbs high frequencies.

Maple's density supports trebles but it is not as stable as an aid against string tension, nearly all guitars have some means of reinforcement. It is possible to include steel rods into the neck which resist the pull from the strings. Further support or reinforcement is found on the soundboard in the form of reinforcing struts or braces.

Figure 2 shows various bracing configurations. Figure 2a shows a torres type bracing. This bracing arrangement provides a reasonably balanced tone and because of the longitudinal struts, is relatively strong. Figures 2b and 2c show a Northern and Southern European bracing arrangement. Because of the lack of longitudinal braces, this design is prone to warpage.

Figure 2d shows the Martin X brace and Figure 2e shows the Gibson double X brace. These designs provide sufficient strength for the soundboard and also produce good treble frequency responses but because of the significant amount of bracing, are not ideal for producing either base frequencies or an overall loud sound.

Figures 2Ff and 2g show theoretical bracing patterns. Figure 2f shows a radial bracing pattern, that is radial from the bridge and Figure 2g shows a grid type arrangement.

The range of frequencies produced by guitars range from a fundamental low of cps to a fundamental high of 1,000 cps. The harmonic and partlals extend this range to over 3,000 cps. Since low frequencies possess characteristics which differ from high frequencies, attention must be paid to the bracing configuration chosen. A major concern in acoustic guitar research is the study of vibrations of the soundboard. The behaviour of the travelling waves is applicable to all parts of guitar: strings, box, neck, etc. When waves meet each other, they will interact and set up nodal patterns.

When playing an instrument it is possible that parts of the instrument will vibrate by chance at the natural resonant frequency of the instrument. Therefore, at points of natural resonance, notes being produced in these regions are often emphasized in an unwelcome way. This can lead to the production of wolf notes, which are an undesired feature of instrument design. An instrument with an uneven response is difficult to play smoothly.

It is the matter of a resonance factor that makes some form of bracing mandatory. A soundboard left free to vibrate would have too distinct peaks of amplitude. A means of dampening the nodal areas of a natural resonance mode is a solution to create a balance of volume.

It can be observed that the nodal points of circular vibrating plates extend in a radial fashion. In many studies of vibrating instrument tops, the paths of energy emanating from a bridge has been detected. Again, there is a tendency for nodal areas to appear as radii from the bridge location. Therefore, if the bracing is radial, as seen in Figure 2f, it would create the situation of aiding the formation of nodal patterns of corresponding frequencies and producing an anti-nodal character at the remaining frequencies. This is therefore clearly undesirable and produces an instrument without an even response.

Therefore, it has been theorized that a grid bracing pattern as seen in Figure 2g would lead to the ultimate bracing configuration for an even response. However, grid type bracing arrangements to date have not been used because they severely dampen the soundboard and limit the vibrations that can be produced, thus creating an instrument that is unable to produce a sufficient amount of sound.

Turning now to Figure 3, there is seen the underside 18 of a soundboard 13 comprising a grid arrangement according to one aspect of the present invention.

The soundhole 14 of the soundboard can also be seen.

The bracing arrangement comprises a grid type bracing arrangement 19 and two harmonic bars 20 and 21 placed on either side of the soundhole 14. This can also clearly be seen in Figures 4a-c which show a top view and two side views of the soundboard with the bracing configuration. The grid arrangement 19 is made up from a series of longitudinally aligned braces 22 and a series of orthogonally aligned braces 23. It can be seen that the grid type arrangement is symmetrical about the axis of the soundboard and extends nearly to the edge of the soundboard.

The braces are tapered at the ends 24. This achieves a number of objectives.

Firstly, the edge of the soundboard is left to vibrate more freely, which helps to produce base tones in the instrument. Secondly, if the brace was to end abruptly it would create a tension point on the instrument which is likely to fracture at that point and will also adversely affect the quality of the sound. While the braces are sometimes shown extending slightly beyond the edge of the soundboard, in practice they would be within the boundary of the soundboard and could also stop a distance before the edge of the soundboard.

It can be seen that the braces further comprise a series of recesses 25. These recesses take the form of semicircular arches through the brace. Looking at Figure 4C it can be seen that the brace resembles that of a conventional road bridge with archways through which water would flow. It can be seen that the longitudinal braces comprise archways in the part of the brace that contacts or abuts the underside face 18 of the soundboard 13. These have been identified by reference 26. The orthogonal braces have the recesses 26 but also have recesses 27 in the part of the brace that faces away from the soundboard. It can also be seen that the recesses 26 and the recesses 27 coincide where the braces overlap. This can be seen all over the grid, for example at position 28. This conjunction of the recesses ensures that the braces do not touch each other. That is, although the braces are arranged in an overlapping grid construction, each brace is separated from its neighbours. The braces themselves are attached to the underside of the soundboard. This can be achieved by a variety of means including glue.

This overlap can more clearly be seen in Figure 5 where the longitudinal braces 22 overlap with the orthogonal braces 23 at position 28, The recesses in the portion of the brace abutting the soundboard are aligned with the recesses facing away from the soundboard in overlapping braces. It can clearly be seen that the braces do not touch each other as a separation is maintained between them.

Figure 4 also shows some other advantageous features of the present design. It can be seen that the grid arrangement defines a series of regions on the soundboard. Reference 29 shows some of the regions that are fully enclosed by overlapping braces. Reference 30 shows regions which are generally enclosed on three sides. It can be seen that these regions are defined by the brace arrangement. Figure 5 clearly shows that each region has recesses in the braces that define its sides. For example, region 29 is enclosed on all four sides and has a recess in each side. it can be seen that region 30 only has one recess leading into it, but it should be noted that the tapered ends of the braces allow the sound to travel past them easily.

The regions are all connected to each other via the various recesses. This gives rise to some interesting tonal properties in that whilst the oscillations may be contained within a region, they still affect neighbouring regions by virtue of the fact that the waves can travel easily through the recesses. It is believed that the sound can enter the grid system and then travel through it from region to region with interference patterns being set up in each grid due to the fact that the soundwaves are entering via a plurality of recesses. It is believed that the soundwaves spread out upon leaving each recess, creating an interference pattern in each region but this effect is then modified by the soundwaves travelling in from other recesses, thus creating an even tone across the surface of the soundboard. It is believed that the waves will travel backwards and forwards across the grid travelling through the recesses and creating specific regions which are vibrating at different frequencies to create different sounds at different tones.

There are essentially two main types of recesses in the strut. There are those that are used to prevent overlapping braces from touching each other and those that are used to allow the soundwaves to travel through the braces. The recesses design prevent overlapping braces from touching should be positioned at the intersection of each brace. It should be noted that the recesses between overlapping struts, that is those that allow access into the regions are aligned with each other. It can be seen that along line A-A in figure 3, the recesses are all aligned with each other, This includes both the recesses in the grid system and also the recesses on the harmonic bars. This alignment allows for the soundwaves and consequently the sound to travel easily through the soundbox and out of the soundhole. By placing recesses in the harmonic bar 20, the sound can easily escape out of the soundhole 14. Equally, by placing recesses in the harmonic bar 21, the sound can travel both into the region at the top of the soundboard and also out of it through the soundhole.

It can be seen that the bracing configuration in Figure 3 gives rise to different regions of stiffness on the soundboard. Within the grid system itself, the soundboard will be quite stiff and will not vibrate easily. This is because it is reasonably well held in place by the struts. Without the recesses, this arrangement would be too stiff and would lead to a guitar that is too quiet. This stiff region is ideal for producing treble tones in the guitar.

At the upper end of the soundboard 32 there is more flexibility in the soundboard because there are less braces and no longitudinal braces. This region is ideal for the production of the mid-range sounds in guitars.

Finally, the region around the outside of the grid system 33 has the most flexibility and is ideal for the production of base tones.

Thus, the grid arrangement in Figure 3 has the advantage that it separates out the base, mid-range and treble sounds, giving a "three- dimensional" sound. By separating out the sounds the instrument is clear and it can easily accommodate the entire range of notes that are required, all at an acceptable volume. By adjusting the arrangement of the struts you can modify the sounds that are produced.

Figure 5 also shows a member 33 attached to the underside 34 of a recess. This member can be made from a pliable material and attached to the underside of said recess. Such materials include, but are not limited to, carbon or thin wood. The member may be attached by a glue or other sealing element. The width that this member extends proud of the brace can be adjusted and also the extent to which it covers the underside of the recess. That is, the member could be substantially half cylindrical or could more preferably not extend fully down the sides of the recess so that it does not touch the soundboard. This member helps to tunnel the sound and all the waves through the recess and into the adjoining regions. For clarity, only one member has been shown but the bracing system could comprise such members in some or all of the recesses.

Another feature of the present invention is shown in Figure 4A. This is a groove 35 which runs around at least a portion of the perimeter of the soundboard. This groove is a channel which is in the region of 1 mm deep and is used to reflect sound back into the grid and away from the sidewalls. It can also be seen that the groove extends into the grid itself with groove 36. Again, only one of the grooves has been shown for clarity but the grooves could travel through some or all of the regions. It is envisaged that groove 36 would travel underneath the recesses. The purpose of these grooves is to help channel the sound through the soundboard and out of the soundbox.

Figure 6 shows a top view and side view of the grid arrangement and Figure 7 shows some of the various braces used in the grid system. In order to maintain a domed shape for the soundboard it is necessary to alter the sizes of the braces.

Figures 7a and 7b show the harmonic bars while figures 7c and 7d show the longitudinal and orthogonal braces. It can thus be seen that the braces shown are of varying heights and have different tapers to their ends. Figure 7d shows an example of an orthogonal brace that comprises both recesses in the bottom 26 and recesses in the top 27.

It can be seen that the recesses do not extend to the edge of the brace. For example in figure 7c, there is material above the top portion of the recess. It is possible to plane the brace to remove as much material as possible from the brace in order to maximise its flexibility without adversely affecting Its strength.

Figures 8a-d show various stages of the construction of a guitar according to the present invention. Figure 8a shows the material used for the soundboard before it has been cut into shape with the grid bracing system placed on top of it. It should be noted that the ends of the braces have not yet been tapered or scalloped. Figure Sb shows a further stage of development in that the soundboard has been cut to shape. Please note that in this particular guitar the top of the soundboard has been cut away to form a shoulder 37. This is down to personal preference and is not necessary to put the invention into effect. In addition to the cut- out soundboard, the harmonic bars have also been put into position and the ends of the grids have been cut to shape. It should also be noted that a groove 35 has been cut into the soundboard around its outer edge in the part where the grid is placed. Figure 8c shows the guitar taking shape with the neck in position and Figure 8d shows the sidewalls being put into place.

Figure 9 shows a soundboard with a grid system in place according to a further embodiment of the present invention. It can be seen that there are a number of differences when compared to the guitar as shown in figure 8. The main change is that the soundboard no longer has a traditional soundhole. Instead, new soundholes are cut out in the upper part of the guitar. They can be seen as reference 41. An ornate pattern is shown butthey can take any shape.

Because the traditional soundhole has been removed, there is a larger soundboard area in the middle of the soundboard. This means that it is possible to have a larger grid system which extends into the region where the soundhole used to be. This can be achieved with more braces and/or longer braces or a complete repositioning of the grid arrangement.

The grid arrangement does not run longitudinally and orthogonally with respect to the neck (not shown). Instead, it runs at 45 degrees. Therefore the present invention is applicable to a grid system which is placed at an angle other than parallel with the strings. Preferably an angle range of 15-75 degrees is used, more preferably 25-65, even more preferably 35 to 55 and particularly preferably 40 to 50 degrees. A particularly preferred angle is 45 degrees or thereabouts. Since there is no soundhole, the tensions on the soundboard are greatly reduced. Looking at figure 3 you can see the traditional soundhole 14 surrounded by harmonic bars 20 and 21. This arrangement leads to increased stress in this region. It also reduces the potential vibrations in the area around the soundhole which can affect the quality and volume of sound produced. Without the soundhole there is less tension on the soundboard and it is not necessary to run the braces longitudinally to take this strain. Instead, they can sit at a different angle (in this case 45 degrees). This means that the grid can be placed to maximise the sound potential and create favourable vibrations across the entire surface of the soundboard.

Furthermore, it can be seen that the same type of brace is used for each strut.

When the brace system needs to counter the strain placed on the soundboard by the strings it is desirable to make the longitudinal struts stronger than the orthogonal ones. This can be achieved by putting recesses in one side only of the longitudinal ones. However, in this system, all braces have recesses in both the bottom and the top.

A further aspect of the present invention is shown in figure 10. In order to provide the necessary strength to support the strings a frame 50 is used. The frame is attached to the neck 51 and runs direct from the neck/body joint. Referring again to figure 3, which shows a sound board of a steel guitar, it shows the harmonic bars 20, 21 to each side of the soundhole 14. This is the traditional way of constructing a guitar and is how most guitars are constructed today. An advantage of using the frame is that it does not require harmonic bars to support the soundhole (since there is no soundhole in the centre of the soundboard). These features cause stress to this part of the guitar, which in turn causes loss of energy from the soundboard.

This energy loss is between the soundhole and the bridge, and simply because of this soundhole positioning, this area of the soundboard is weakened. It is also believed that this stops a lot of sound frequency transferal from the nodal ends i.e. string ends nut/saddle where the strings start and finish. This is important for the transferal of sound frequencies to be able to travel from one end of the string down the neck of the guitar into the soundboard, as it is from the other end of the string into the saddle/bridge. With a soundhole, sound cannot travel through this soundhole instead it dissipates into each side of the guitar around the soundhole and into the sides and back of the guitar. This unfortunate characteristic is a feature of guitar construction today Figure 10 shows the new frame. It connects directly from the neck/fingerboard of the guitar directly to the soundboard area. The main purpose of the frame is to take the stresses from the string tension so that they are not transmitted to the soundboard. The forces are absorbed by the frame, which means that they are not transmitted to the soundboard. This means that the bracing system on the frame do not need counter the forces from the strings. The bracing system instead is used to take the strain from the bridge and to transmit the soundwaves across the soundboard in the desired manner. In essence, the frame provides the strength and the bracing system provides the desired sound effects.

The frame itself is an A shape or tennis racquet shape, it has a half inch lip around the outer edge exactly like a drum rim. The width of the frame on the underside is approx. one and a quarter inches wide. This is routed out to a depth of approx. three eighths of an inch. As can be seen from figure 10, this creates a gap between the underside of the soundboard and frame. This has an advantage in that the frequencies can bounce back and forth from the soundboard to give a good sustained sound. As stated above, the frame also takes the forces from the string tension leaving the bracing system to be designed and positioned to create the optimum sound effects.

Figure 11 shows the guitar with the frame and soundboard in position. It can be seen that the frame sits over the soundboard (with the gap visible) . The shape of the frame fits with the profile of the sidewalls and therefore fits neatly into the sound chamber. The soundholes are provided on either side of the frame near the neck.

Figure 12 shows the backboard. It can be seen that some bracing at a 45 degree angle has also be put on the backboard. This provides additional strength and also changes the sound properties of the backboard. The guitar can be provided with our without this additional bracing.

Figure 13 shows a guitar according to a further embodiment near completion. It can be seen that the soundholes are placed near the neck of the guitar and that the whole middle section is clear since there is no central soundhole. This leads to a better sounding guitar with increased responsiveness and/or increased volume.

It should be understood that the present invention encompasses a novel bracing system as well as novel braces comprising recesses. The example has been given of a guitar incorporating such a system but the invention is equally applicable to other musical instruments. It has been discovered that the musical instrument has a very different sound to other instruments incorporating different bracing systems. In terms of the amplification or volume of the sound, the bracing system increased the volume of the instrument by a considerable degree but especially brought out the mid-range and treble. With regard to the transient tone (the ability to play the instrument quickly) the instrument had a very open and individual sound and not at all muffled. This was a significant disadvantage with prior art bracing systems because in order to get an increased volume and base the sound ended up quite muddled because the soundboard could vibrate in a sloppy way, losing the mid- range and treble and also losing control of the vibration and nodes on the soundboard. Were a grid system to be employed without the recesses, the grid would be too quiet and there would be not enough base. With the recess system it is believed that by adjusting the width of the arches the sound quality can be changed, for example increasing the bass by widening the arches.

The sound itself is very different in the musical instrument in that for a given note that is played, various "harmonic" sounds can also be heard. It is believed that this is either caused by the note sounding so purely that the additional harmonic sounds can now be heard or alternatively or in addition, that the brace is creating artificial harmonics1 that is the grids could amplify certain harmonics thus making them better heard. This creates a very interesting sound in that when playing one note various other complementary harmonic notes can also be heard at the same time. This has a very beneficial effect on the sound of the instrument.

The brace also affects the sustain of the note. It has been noticed that the sustain is very good in that the sustain plateaux instead of dying away. In a normal instrument when the string is plucked the noise produced initially increases and then fades away. In the present invention, however, the noise increases and then plateaux and stays at a given volume for longer before dying away. This gives an interesting sound to the instrument. The sustain is especially noticeable on the mid- range and treble which is ideal for a classical guitar. There is a perception that the volume of the note actually increases before fading away.

The brace also affects the brilliance of the instrument, especially the mid-range and treble.

The grid system incorporating the braces will drastically improve the strength of the guitar and therefore its longevity. It is believed that a guitar made according to the current invention should last much longer in comparison to a normal guitar.

The present invention is both applicable to steel strung guitars and also classical guitars which incorporate nylon strings. Because nylon strings are used on classical guitars at lower tension the sound they produce is also correspondingly lower.

Nylon strings are used to be easier on the fingers. The present invention is suited to both types of instrument with regard to the classical guitar, it helps increase the volume of the instrument which is particularly useful.

The frame system is applicable to both classical or steel strung guitars and is particularly applicable to classical guitars. Because of the lower tension in a classical guitar, the bracing system does not need to run parallel with the strings to support them. Thus a grid arraignment at 45, or any other angle is available.

In summary, the present invention shows that it is possible to put recesses in a brace. This can be usefully, but not exclusively, incorporated into a grid system which produces an idea sound for an instrument. In one example, the grid system produces a total of eight squares or regions, defined by the overlapping braces.

The grid Is made from struts or braces of wood jointed together to make a series of squares. The grid is useful for supporting and holding a dome shape to the top of the guitar. A grid system has been desired for a long time but has never been successful. This is due to the stiffness which results in a generally quiet sound due to a loss of power. However, the stiffness does give an even response to the sound in the guitar.

The present invention can be thought of as employing the same ideas as when a pebble is dropped into a pond creating an oscillating pattern or wave. As the sound frequencies hit the soundboard, they splay out along its surface, travelling from one grid to the next and so on. Because of the open recesses or archways from any side of the grid, the soundwaves can travel easily between adjacent regions. The end result is a clean, powerful harmonic sound. If a normal grid system were used, the waves would be contained to each grid and would be locked into each individual square.

In addition, the present grid is flexible. Prior art grids were joined together as a single solid construction of half laped joins. Therefore, conventional grids were too stiff. The present invention is far more flexible but is strong in a longitudinal direction to hold a string tension of approximately 175 lb. This is achieved by using the recesses or archways themselves to prevent the braces touching each other where they cross over. The only places where the struts or braces touch is where they are glued to the soundboard. The braces going horizontal or longitudinal only require recesses in the bottom of the braces, so when they are glued to the soundboard they are very rigid, which is necessary to hold the tension in the string. When the braces travel orthogonally across the soundboard, or from side to side, the recesses are reversed so that they are in the top of the brace. It is also possible for recesses to be formed in the bottom of these braces in addition to those in the top. This arrangement is such that overlapping braces do not touch each other because the recesses in the bottom and top are arranged such that they meet each other at the crossover points. This system creates flexibility in the orthogonal struts and this allows the grid to move in order to make the soundboard work efficiently.

However, when the grid system is not parallel to the strings the struts can be of the same strength. Therefore, all struts can have recesses in the top and the bottom.

The present invention covers any particular arrangement of grids. One examples of this are where the grid systems runs longitudinal and orthogonal to the neck, the other is where the grid is placed at an angle to the string direction, e.g. 45 degrees.

Both systems have different properties. A longitudinal grid provides greater strength to counter the tension from the strings but where this is not necessary or is not as necessary, an angled grid allows for different sound characteristics.

Claims (46)

1. A brace for the soundboard of a musical instrument wherein the brace incorporates recesses.

2. A brace according to any preceding claim wherein the recesses can be adjusted to change the sound produced by the instrument.

3. A brace according to any preceding claim wherein the recesses comprise substantially semicircular archways through the brace.

4. A brace according to any preceding claim wherein the recesses are substantially oval or substantially square.

5. A brace according to any preceding claim wherein the brace contains between 1 and 20 recesses.

6. A brace according to any preceding claim wherein the brace contains between 2 and 15 recesses.

7. A brace according to any preceding claim wherein the brace contains between 3 and 10 recesses.

8. A brace according to any preceding claim wherein the recesses are formed in the bottom portion of the brace to be connected to the soundboard.

9. A brace according to any preceding claim wherein the recesses are formed in the top portion of the brace not connected to the soundboard.

10. A brace according to any preceding claim wherein the recesses are formed in both the bottom portion of the brace connected to the soundboard and the top portion of the brace not connected to the soundboard.

11. Bracing according to Claim 10 whereIn when two braces overlap, at the position where they overlap a recess in the top portion of a first brace and a recess in the bottom portion of a second brace coincide, such that the two braces do not touch each other.

12. Bracing according to any preceding claim wherein the recesses in the braces are aligned.

13. A brace according to any preceding claim wherein the recess is defined by an inner surface in the brace and the brace further comprises a member adapted to connect to said inner surface and extend beyond the width of the brace.

14. Bracing according to any preceding claim wherein the braces include harmonic bars and the harmonic bars contain recesses.

15. Bracing according to Claim 14 wherein the recesses in the harmonic bars are aligned with at least some of the recesses in the rest of the bracing.

16. Bracing according to any preceding claim wherein the bracing comprises longitudinally aligned and orthogonally aligned braces with respect to the body of the instrument.

17. Bracing according to Claim 16 wherein the orthogonal braces are more flexible than the longitudinal braces.

18. Bracing according to Claim 16 or Claim 17 wherein the orthogonal braces comprise more recesses than the longitudinal braces.

19. A brace according to any preceding claim wherein the brace comprises scalloped ends.

20. Bracing according to any preceding claim wherein the braces are arranged in a grid arrangement.

21. Bracing according to Claim 20 wherein the grid is aligned longitudinally and orthogonally with respect to the body of the instrument.

22. Bracing according to Claim 20 or Claim 21 wherein the grid is substantially symmetrical about the longitudinal axis of the instrument.

23. Bracing according to any of Claims 20 to 22 inclusive wherein the braces define a series of regions and each region has at least one recess leading into it.

24. Bracing according to Claim 23 wherein each side of each region is defined by a brace containing a recess.

25. A soundboard attached to a brace according to any preceding claim.

26. A soundboard according to Claim 25, wherein the soundboard further comprises a groove or grooves.

27. A soundboard according to Claim 26 wherein the groove(s) run(s) around at least a portion of the perimeter of the soundboard.

28. A soundboard according to claim 26 or 27 wherein the groove(s) extends through one or more of the recesses in the braces.

29. A soundboard according to any of claims 26 to 28 inclusive wherein the groove(s) extends longitudinally up the soundboard.

30. A soundboard according to any of claims 25 to 29 inclusive wherein the soundboard is domed.

31. A soundboard according to any of claims 25 to 29 inclusive wherein the soundboard is flat.

32. A soundboard according to any of claims 25 to 31 wherein the soundboard is less than 3mm thick.

33. A soundboard according to any of claims 25 to 31 wherein the soundboard is less than 2mm thick.

34. A soundboard according to any of claims 25 to 31 wherein the soundboard is less than 1.8mm thick.

35. A brace according to any preceding claim wherein the musical instrument is a guitar.

36. A brace according to any Claim 35 wherein the guitar is a steel stringed guitar.

37. A brace according to Claim 35 wherein the guitar is a classical guitar.

38. A brace according to any of claims I to 34 inclusive wherein the musical instrument is selected from the group consisting of a violin, viola, cello, double bass, acoustic bass, or jazz guitar.

39. A bracing arrangement for the soundboard of a musical instrument wherein at least some of the braces overlap each other characterised in that the braces are configured not to touch each other in the overlapping region.

40. A bracing arrangement according to Claim 39 using bracing as defined in any of claims 1 to 38.

41. A bracing arrangement for the soundboard of a musical instrument wherein the braces comprise longitudinally aligned and orthogonally aligned braces with respect to the body of the instrument characterised in that the orthogonal braces are more flexible than the longitudinal braces.

42. A bracing arrangement according to Claim 41 using bracing as defined in any of claims 1 to 38.

43. A musical instrument comprising at least one brace according to any preceding claim.

44. A guitar comprising at least one brace according to any preceding claim.

45. A brace as hereinbefore described and with reference to the accompanying drawings, excluding figure 2.

46. A musical instrument as hereinbefore described and with reference to the accompanying drawings, excluding figure 2.