FR3100366A1 - Electronic piano - Google Patents

Abstract

Electronic piano comprising a housing (1), a keyboard (7) comprising a plurality of mechanically actuated keys, and a loudspeaker (6) capable of generating acoustic vibrations, which are at least partially received in said housing (1) , said piano being characterized in that it further comprises a vibratory transfer member (2) capable of transferring the vibrations emitted by the loudspeaker (6) towards the keyboard (7), this vibratory transfer member (2) ) comprising a front transverse zone, intended for the support of the keyboard, and a rear transverse zone intended for the reception of the loudspeaker (6), said respectively front and rear zones being mutually connected so that at least a substantial part of the vibrations generated by the loudspeaker (6), at the level of the rear zone, are transmitted in the direction of the keyboard (7) located at the level of the front zone.

Description

electronic piano

Technical field of the invention

The invention belongs to the technical field of electronic pianos, in which the sound, caused by the actuation of the keyboard, is generated by a digital processor associated with an acoustic loudspeaker. Such an electronic piano can imitate the sound of an acoustic piano.

State of the art

In an electronic piano the sound is generated electronically; such a piano does not have strings set in vibration by the actuation of the keys, but the keys are provided with sensors which transmit a signal to an electronic component forming part of an electronic system which generates an analog electrical signal transmitted to a loudspeaker -speaker, which can be built into the piano or external. The integration of loudspeakers in the case of the keyboard is known from US 5,308,937 (Kabushiki Kashia Kawai Gakki), and many instruments on the market have loudspeakers which are integrated into the case of the electronic keyboard.

There are electronic pianos whose sound quality and touch are quite similar to those of acoustic pianos (i.e. in which the sound is generated by the action of a hammer which is projected on one or more strings when the pianist operates a key ) small or medium-sized, and in particular good quality upright pianos; these electronic instruments are commercially available. It has now appeared the desire to have an electronic piano which presents both the same quality of sound reproduction, the same possibilities of mastering the sound by the touch of the pianist, and the same acoustic and tactile sensations felt by the pianist, than the best concert grand pianos. Such an electronic piano does not yet exist; it is hoped that it can be cheaper and easier to transport than a concert grand piano, the length of which can exceed 2.6 meters and the mass can exceed 450 kg.

The tactile sensations felt by the pianist depend, on the one hand, on the keyboard itself, i.e. on the construction, the mass, the movement of depression, the end of travel and the return movement of the keys, and, on on the other hand, by the vibrations that the instrument as a whole transmits to the keys, which are, apart from the pedals, the only material point of contact between the pianist and his instrument. These vibrations, perceived by the pianist first at the tips of his fingers which are the points of contact with the keys of the keyboard, can then be felt in other parts of the finger, and can spread to different parts of the hand and of the arm. It is a global sensation, due to the vibration of the entire structure of the piano. For a very high level player, this vibrational feedback is complementary information (compared to the acoustic rendering which constitutes the main information) quite interesting and usable, and can also be a source of pleasure.

Thus, the absence of vibrations transmitted from the instrument to the keyboard is normally only noticeable to a good pianist who has practiced top quality acoustic pianos. This lack appeared as the restitution of the sound quality of electronic pianos improved enough for electronic pianos to be of interest to very good level pianists. The state of the art presents several approaches.

US 5,189,242 (Yamaha) describes an electronic piano in which the keyboard is placed on a resonance plate which can be vibrated by an electric vibration generator. These vibrations are transmitted to the keyboard. However, these vibrations are not generated by the sound as it is generated by the piano under the action of the pianist; the pianist will therefore not have the same feeling of vibrational feedback in relation to the sound he has just produced as on a good quality acoustic piano.

US 2010/0147132 and US 2010/0147131 (Yamaha) describe an electronic piano which takes the form of a grand piano (of so-called "quarter grand" size), and which is provided with a resonance plate. JP 2011/043 611 (Yamaha) describes an electronic piano in which the keyboard is mounted in a complex structure formed of folded and screwed sheets, which transmits vibrations generated by a vibrator to the keyboard box and to the keyboard. Mechanically, this structure is very complex.

The problem that the present invention seeks to solve is to present an electronic piano of excellent acoustic quality, comparable to that of a concert grand piano, which ensures a vibratory transfer to the whole of the structure and to the keyboard, with a result felt by the pianist which is comparable to that obtained on an excellent acoustic piano, and which is easy to manufacture and assemble.

Objects of the invention

According to the invention, the problem is solved by integrating the various functions of the keyboard support structure into a section on which the keyboard is fixed, directly or by means of a support plate, and in which insert at least one loudspeaker. Said profile can be a metal profile (for example an extruded profile of aluminum alloy), or a profile of non-metallic material (for example carbon fiber). The combination of these means ensures a good transfer of the vibrations from the loudspeaker to the structure.

Thus, a first object of the invention is an electronic piano comprising a casing or casing, a keyboard comprising a plurality of mechanically actuated keys, and at least one loudspeaker able to generate acoustic vibrations, which are at least partially received in said box, as well as at least one digital processor able to process the signals coming from the keys and to generate signals transmitted to said at least one loudspeaker,

said piano being characterized in that it further comprises a vibratory transfer member, which is in particular a section, capable of transferring the vibrations emitted by the loudspeaker towards the keyboard,

this vibratory transfer member comprising a front transverse zone, with reference to the user in a gaming situation, intended for receiving the keyboard, and a rear transverse zone intended for receiving the at least one loudspeaker,

said respectively front and rear zones being mutually connected by a mechanical means, so that at least a part, preferably substantial, of the vibrations generated by the loudspeaker, at the level of the rear zone, are transmitted in the direction of the keyboard located in the front area.

Said respectively front and rear transverse zones can be made in one piece, in the transverse direction of the transfer member.

In one embodiment, the respectively front and rear zones belong to respectively front and rear parts of the transfer member, and fastening means are provided between these parts, these fastening means making it possible to ensure vibratory continuity between said front and rear parts.

Advantageously, the reception zone arranged in the vibratory transfer member comprises a chamber which may be open upwards and/or laterally, and which may in particular have a U-shaped cross-section. This chamber may accommodate a loudspeaker . Means for mounting the or each loudspeaker on the walls of the chamber may be provided, in particular at least one mounting member of the flange type. Sealing means can be provided between the interior volume of the chamber and the exterior of this chamber.

The keyboard can be fixed on said front zone of the vibratory transfer member with securing means. Said front zone can comprise a support area for the keyboard. In a variant, an intermediate mounting plate is provided, fixed to said range, the keyboard being secured to this intermediate plate.

The vibration transfer to the structure and the keyboard can be further improved by the use of a loudspeaker integrated into a hermetic loudspeaker enclosure. Advantageously, the volume of said enclosure is undersized. Preferably, two loudspeakers are inserted into the profile, one on the left and one on the right; this makes a spatialized sound like on an acoustic piano.

In a very advantageous embodiment, said loudspeaker enclosure is undersized, and advantageously has a total overvoltage coefficient of at least 0.75, preferentially of at least 0.90, more preferentially of at least 1.1 or 1.2, and even more preferably between 0.90 and 1.5.

According to another embodiment, the keyboard case rests, preferably in a fixed or removable manner, on a base, such as a foot. In this base, one or more additional loudspeakers can be integrated. At least one of these additional loudspeakers may be a bass loudspeaker. The presence of a loudspeaker in the base further improves vibration transfer and makes it more realistic for the pianist, comparable to a concert piano. Advantageously, it is a hermetic loudspeaker, the enclosure of which may be undersized.

The electronic piano according to the invention can be made in a foldable manner. In this case the keyboard case comprises at least two, and preferably three, sections in its longitudinal direction, to be foldable. More specifically, the vibratory transfer member is formed of at least two sections. Thus, each of the sections of the box comprises a section of said vibratory transfer member, which is one of the essential means of the present invention. Two continuous sections of said vibratory transfer member (which is typically a profile) are connected by a movable, removable or foldable mechanical connection means, which can be of the hinge type; this means must ensure, in the unfolded state, a rigid mechanical connection between the two sections of the profile. In order to improve the vibratory transfer, it is possible to add mobile assembly elements in the plane of the keyboard.

Each section of the profile can be in one piece, or it can be assembled across its width from two or more profiles, in particular by clipping, screwing, gluing, welding between two profiles; it is preferred to make the profile in one piece.

The vibration transfer is modified, and in particular damped, by covering the profile to form a keyboard box, knowing that the speed of sound propagation is different in the air, in the covering material (typically wood), and in metal. Specifically, the metal profile provides vibrational transfer from the speaker enclosure to the keyboard, while the cabinet dampens the vibrational transfer of the metal profile into the air to ensure a "rounder" and "deeper" sound. and to avoid unpleasant resonance peaks ("tinny sound").

This covering is advantageously made of wood or synthetic material, for example carbon fiber composite; it can be made by assembling elements using techniques known to piano makers. A wooden cladding is typically assembled from several simple shaped panels, while a synthetic material cladding can take on a more complex shape, such as a shell shape. This damping helps to achieve a feel as close as possible to that emanating from a concert acoustic piano.

Brief description of figures

The invention will be described below, with reference to the accompanying drawings, given solely by way of non-limiting examples, in which:

is a perspective view illustrating an electronic piano according to one embodiment of the invention.

is a perspective view, illustrating more particularly the upper part of this piano.

is a perspective view, illustrating more particularly certain mechanical elements located inside the case of this piano.

is a perspective view, illustrating more particularly a vibratory transfer profile received in this housing.

is a perspective view, with longitudinal section, illustrating in more detail the cooperation between the profile of FIG. 4, as well as a loudspeaker and the keyboard of the piano.

is a view in longitudinal section, illustrating the various mechanical elements shown in Figure 5.

is a perspective view, more particularly illustrating a base belonging to this piano.

The following reference numerals are used in this description.

1 case; 2 body (profile) of vibration transfer;

6 speakers; 7 keyboard; 8 digital processor; 9 base;

10 case back; 11.12 front and rear enclosure walls;

13.14 case sidewalls; 15 upper enclosure walls;

16 opening in the wall 15; 20 profile front area;

22 range; 24 front angle; 26 screws; 28 cells;

40 profile rear area; 42 bedroom; 42a 42b longitudinal end of 42;

44 soul of 42; 46.48 wings of 42;

50 re-entrant shoulder; 52 chute; 53 range; 54 mounting screws; 56 caissons;

60 6 mounting flange; 63 opening in 60;

64 flange of 6; 65 mounting screws; 66 67 68 69 case edges;

72 mounting plate 7 versus 20; 74 additional profile;

76 back from 74; 78 74 rib;

80 reception accommodation of 8; 82 80 hood; 83 adjustment knobs of 82;

84.86 grids; 88 cache;

90, 92 lateral feet of 9; 91, 93 enclosures of 90, 92;

94.95 openings of 91.93; 96, 97 91, 93 speakers; 99 traverse;

XX YY axes and directions respectively longitudinal and transverse of the piano and the profile;

I piano

detailed description

The electronic piano in accordance with the invention, which is illustrated in the attached figures with the reference I assigned to it, essentially comprises the following mechanical elements: a body 1 forming a case, a keyboard 7 , a digital processor 8 , at least one top -loudspeaker 6, a section 2 ensuring the vibratory transfer between the keyboard the loudspeaker, a base 9 .

By convention, we note, in particular in FIGS. 1 and 4, XX and YY the respectively longitudinal and transverse directions of the piano according to the invention. XX corresponds to the largest dimension of this piano (and more precisely to case 1), while YY corresponds to the smallest of these dimensions. XX and YY also correspond to respectively longitudinal and transverse directions of the section 2 . In particular, the direction XX corresponds to the direction of extrusion of this profile.

These directions XX and YY are also associated with respectively longitudinal and transverse axes of this piano. We note in the AV and AR figures the respectively front and rear transverse parts of this piano, with reference to the position of the user in a playing situation. In other words, the front part is adjacent to the user, then that the rear part is opposite to it.

As seen in Figure 1 , the housing 1 , which has a substantially parallelepipedic shape, has a bottom 10 bordered by peripheral walls. The latter comprise respectively front 11 and rear 12 walls, as well as side walls 13 , 14 . Finally, the upper wall 15 is noted, which is hollowed out with an opening 16 which extends over a large part of its surface to give access to the keys of the keyboard 7 . By way of non-limiting example, the constituent material of this casing 1 is, for example, wood. However, as a variant, provision may be made for this casing 1 to be made, at least in part, of synthetic materials, for example of composite materials (in particular of the type comprising carbon fibers), and/or of polymeric material.

The box 1 rests on the base 9 , the structure of which will be explained in greater detail below in relation to figure 7.

As can be seen in FIG. 2 , the profile 2 extends between the side walls 13 and 14 of the casing.

The cross section of this section 2 typically has a substantially constant shape, along its longitudinal axis XX. By way of non-limiting examples, this profile can first be made of a metallic material, such as aluminum or an aluminum alloy (for example an alloy of the Al-Mg-Si type, the alloys of this type being also known as 6xxx), or steel.

Very advantageously, a profile made by extrusion is used, and not a profile obtained by bending sheets; Extrusion (also called spinning) is a process which makes it possible to produce profiles of fairly complex section. As a variant, provision may be made for this profile to be made of a non-metallic material, in particular of a composite material (in particular of the type comprising carbon fibers) or of a plastic material.

Extrusion leads to profiles of constant shape along their long axis (direction of extrusion). It is possible to work this extruded profile by machining and/or by deformation to obtain a profile whose shape is not constant along its long axis. It is also possible to use bent sections, in particular made from sheet metal, and/or welded sections.

This profile2 first of all has a so-called front zone20, turned towards the user in a game situation, which is intended to support the keyboard7. This zone20is made up of a range22, from which extends a front angle24, allowing the fixing of a screw26on the wall11of the case. Immediately below the beach22, different cells28are planned. Their function is to provide sufficient mechanical strength to this part of the section, in particular to allow it to support the mass of the keyboard without significant deformation. In particular, as shown in Figure 6, it is possible to use screws30allowing the profile to be fixed to the bottom10of the box.

As can be seen in particular in FIGS. 4 and 5 , the aforementioned front zone is extended by a rear zone 40 , first of all comprising a U-shaped chamber 42 (also called the “rear chamber”). This chamber 42 is formed of a core 44 , as well as two wings 46 and 48 . One of its wings is provided with a reentrant shoulder 50 , while the other wing extends radially outwards via a channel 52 , allowing the passage of a fixing screw 54 on the wall 13 . This chute also delimits a range 53 , the function of which will be described below. Furthermore, in the extension of the cells 28 along the transverse axis, several boxes 56 separated by stiffeners are provided below the chamber. These boxes allow in particular the fixing on the bottom 10 of the case, in the example illustrated by means of screws 58 . The chamber may include a cover made of wood, metal, or plastic materials, or a combination of several materials.

The box includes two loudspeakers 6 , one on the right side of the box 1 , the other on the left side. Each loudspeaker 6 is mounted on the profile 2 , at the level of a longitudinal end 42a or 42b of the chamber 42 , via a respective flange 60 . In more detail, this flange 60 has the outer shape of a quadrilateral, corresponding to the shape of the upper part of the chamber of this profile. Furthermore, this flange 60 is hollowed out with a central opening 63 , allowing the passage of the loudspeaker 6 . The latter comprises a flange 64 , allowing the support of the loudspeaker against the periphery of this opening 63 . Screws 65 allow removable fixing of both the flange and the loudspeaker, with respect to the profile 2 . For this purpose, these screws cooperate with the shoulder 50 described above. Thus, the loudspeaker 6 is embedded in the rear chamber 42 of the profile 2 . This chamber forms a sound box which extends over the entire longitudinal dimension of the section 2 .

At least part of the covering elements which form the box1, and which can be made of wood and/or synthetic material, are advantageously in contact with the walls of this rear chamber42 : this improves the fidelity of the sound rendered by the electronic piano according to the invention.

As shown in particular in Figure 3 , the housing is provided with several flanges, which extend transversely along the YY axis. Two first flanges 66 , 67 are first provided, adjacent to a respective side wall 13 , 14 of the housing. Furthermore two additional flanges 68 , 69 are provided at a distance from each flange above. Each pair of flanges, respectively 66 , 68 and 67 , 69 , is mutually spaced by a distance corresponding substantially to the dimension of each flange 60 , longitudinally along the axis XX. It is also possible to provide sealing means interposed between the walls facing the flange and this rim.

The keyboard 7 can be of any type known per se, is advantageously a mechanical keyboard, provided with keys which sink under the pressure exerted by the pianist's finger. This keyboard 7 is secured to the range 20 of the section, thanks to an intermediate plate 72 . Furthermore there is provided an additional section 74 , which is fixed to the keyboard. This section 74 is provided with a U-shaped return 76 , as well as an end rib 78 . This return and this rib allow the fixing of both the plate 72 and the keyboard 7 , relative to the profile 2 , by means of additional screws 78 . All the assemblies which have just been described are made by mechanical assembly means, typically by snap-fastening, screwing or riveting.

Said intermediate plate72 is optional; it has several advantages. It acts as a stiffener for the structure of the box1, it facilitates the assembly of the keyboard7on the vibration transfer device2, it promotes vibrational transfer.

It is possible to use a plate made of rolled sheet of aluminum alloy, preferably an alloy with age hardening, even more preferably in a solutionized and tempered state. As such, it is possible to use, for example, an alloy sheet of the Al-Zn-Mg-Cu type.

The digital processor 8 can be of any type known per se. This processor is received within a middle housing 80 , with reference to the YY axis. This housing 80 is bordered, on either side, by the flanges 67 and 69 , as well as the facing walls of the flanges 60 . The processor 8 is connected, by any suitable means, to both the loudspeaker and to the keyboard. These various connections, which are of a type known per se, are not detailed in what follows.

The processor receiving slot is covered by means of a cover 82 . The latter may comprise one or more adjustment buttons 83 , of a type known per se; it may be in particular an adjustment of the sound volume.

Furthermore, the upper face of each loudspeaker 6 is covered by a grid 84 , 86 , which is fixed to a respective flange by any suitable means, in particular by screwing. Finally, a cover 88 , of elongated shape, extends along the YY axis between the keyboard and the rear area of the case.

As can be seen on thefigure 7, the base9, fitted to the piano in accordance with the invention, comprises first of all lateral feet90,92. The bottom10of the case rests on the top of these feet, being fixed to the latter by any suitable means, in particular in a removable manner. The internal face of each foot, namely that which faces the opposite foot, supports a respective enclosure91,93. Each enclosure defines a central opening94,95, intended for the reception of a respective loudspeaker96,97. Each loudspeaker is fixed on the periphery of its reception opening, by any appropriate means such as for example screws. Finally the feet90And92are mutually connected, at their rear area, by a crosspiece99. The speaker(s)96,97 located in the side feet are typically intended for low frequencies.

Alternatively, a single loudspeaker can be provided in the base. In this case, said loudspeaker is preferably arranged so that it sends the sound waves onto a flat surface (typically on the opposite foot) to generate sound rebounds. More specifically, said loudspeaker can be mounted on an internal surface on one side of said base, and the internal face opposite said loudspeaker has a flat surface, so that the sound waves emitted by the membrane of said loudspeaker speaker can be returned by said flat surface.

In this embodiment, the case is foldable, that is to say the case, the profile and the keyboard are each formed by three sections, placed one behind the other longitudinally along the axis XX. In the figures these different sections are referenced 1A to 1C, 2A to 2C as well as 7A to 7C. More specifically, there is a fixed central section, as well as end sections, which are provided on either side of the central section. Preferably, the two mobile sections 1A, 1C, 2A, 2C, 7A, 7C have the same length, which is equal to at most half the length of the central section 1B, 2B, 7B. In this way, when the piano is folded, the outer edges of the movable sections are mutually adjacent.

In order to allow such an embodiment, the piano is equipped with reversible mechanical fastening means provided at the junction between the facing edges of the central section and a respective end section. The reversibility of these fastening means allows the user to easily fold and unfold the box, preferably without tools.

These reversible fixing means can be hinges. By way of non-limiting examples, these articulation hinges are for example in accordance with those which are described in WO 2018/185841 in the name of the applicant. Of course, other hinge structures and more generally other reversible mechanical fastening means can be provided, for example snap-fastening means, or even magnetic means.

We have seen above that, in the present embodiment, the profile2 is made in three sections, along its longitudinal direction XX. Within each section this section2is made in one piece, in its transverse direction YY. This allows a satisfactory transfer of vibrations, from the loudspeaker6towards the keyboard7. On the one hand, the mechanical fastening means contribute to the vibration transfer between the different sections of the profile2, as well as between the different sections of the profile2and the box1. On the other hand, the mechanical fixing of the keyboard7on the profile2 ensures the vibratory transfer from the profile to the keyboard. These vibrations originate in the loudspeakers6integrated in the profile2(in the case of a foldable box with three sections: typically in the right section and the left section); they are transferred from the loudspeakers6to profile2, then towards the walls of the case1, and finally to the keyboard7.

As a variant (not shown in the figures), it is possible for the casing 1 to comprise only two sections, or a single section (in the latter case it is not foldable).

According to the invention, the vibration transfer member is made in the form of a profile2, which is received in a box1. This is advantageous, in particular in terms of simplicity of manufacture. It is this organ2 vibration transfer which ensures for a significant part the transfer of the vibrations of the sound generated by the loudspeakers6integrated in the housing1to the keyboard7, which is also received in said box1. The constituent material of said case contributes to the vibratory transfer of the sound generated by the loudspeaker to the keyboard. This transfer also takes place by air, and this is more effective if the box is closed, as is the case in the embodiments shown in the figures.

According to another aspect of the invention, the loudspeaker enclosure 6 is a closed enclosure (such enclosures are also known under the name “hermetic enclosure”). Advantageously, it is undersized, that is to say its volume is such that its total overvoltage coefficient is greater than 0.707. This undersizing forces a significant part of the sound power to flow through the structure of the piano (in this case, through the profile) and not through the air vibrated by the speaker membrane.

The inventors have found that the overvoltage coefficient can be significantly greater than 1.1. By way of example, an electronic piano according to the invention has been produced having speakers integrated into the profile 2 with an overvoltage coefficient of approximately 1.37. More generally, the overvoltage coefficient is advantageously between 1.1 and 1.5.

By way of example, an electronic piano according to the invention has been produced with two loudspeakers6identical, embedded in the profile2, each comprising a closed enclosure, said loudspeaker being designed to operate optimally with a closed enclosure with a volume of 3.7 liters, whereas the volume of the closed enclosure in the electronic piano according to the invention n was only 2.7 liters. A very satisfactory vibration transfer was obtained, even in the case where the profile2 comprised three sections mechanically connected by hinges.

Preferably, the orientation of the loudspeakers embedded in the section 2 is such that the vibrating membrane is horizontal so that the emission of the sound is upwards; however, an inclination can also be provided.

As indicated above, it is advantageous to add to the loudspeaker recessed in the profile2 (or to the two loudspeakers recessed in said profile) a third (or even a fourth) loudspeaker dedicated to low frequencies; this loudspeaker can be integrated into the base of the piano. This improves both the sound delivered by the piano and the vibrational transfer to the keyboard. Only one loudspeaker can be used in the base.

Claims (13)

Electronic piano including

• a box (1) or casing,
• a keyboard (7) comprising a plurality of mechanically actuated keys, and
• at least one loudspeaker (6) able to generate acoustic vibrations,

which are at least partially received in said box (1), as well as at least one digital processor able to process the signals coming from the keys and to generate signals transmitted to said at least one loudspeaker (6),
said piano being characterized in that it further comprises a vibratory transfer member (2), which is in particular a section, capable of transferring the vibrations emitted by the loudspeaker (6) towards the keyboard (7),
this vibratory transfer member (2) comprising: a front transverse zone (20), with reference to the user in a game situation, intended to receive the keyboard (7), and a rear transverse zone (40) intended to reception of at least one loudspeaker (6),
said respectively front (20) and rear (40) zones being mutually connected so that at least part of the vibrations generated by the loudspeaker (6), at the level of the rear zone (40), are transmitted in the direction of the keyboard (7) located at the level of the front zone (20). Electronic piano according to the preceding claim, in which the front (20) and rear (40) transverse zones respectively are made in one piece, in the transverse direction (YY) of the vibratory transfer member (2). Electronic piano according to Claim 1, in which the respectively front (20) and rear (40) zones belong to respectively front and rear parts of the vibratory transfer member (2), and fastening means are provided between these parts, these fastening means making it possible to ensure vibratory continuity between said front (20) and rear (40) parts. Electronic piano according to one of the preceding claims, in which the rear zone of the said vibratory transfer member comprises a rear chamber (42), which can be open upwards and/or or laterally, and which can in particular have a section U-shaped cross section. Electronic piano according to one of the preceding claims, characterized in that the said at least one loudspeaker (6) received in the said vibratory transfer member (2) is integrated into a sealed loudspeaker enclosure. Electronic piano according to Claim 5, characterized in that the said loudspeaker enclosure (6) is undersized, and advantageously has a total overvoltage coefficient of at least 1.1, preferentially of at least 0.90 and which is more preferably between 1.1 and 1.5. Electronic piano according to one of the preceding claims, further comprising means for securing the keyboard (7) to the front zone. Electronic piano according to one of the preceding claims, in which the front transverse zone comprises a keyboard support area (7). Electronic piano according to the preceding claim, in which an intermediate assembly plate (72) is provided, fixed to the said track, the keyboard (7) being secured to this intermediate plate (72). Electronic piano according to one of the preceding claims, in which the vibratory transfer member (2) is formed of at least two sections, in its longitudinal direction, two adjacent sections being mutually connected by a mechanical connection means movable, removable or foldable, in particular by a hinge. Electronic piano according to one of the preceding claims, further comprising a base (9), as well as at least one additional loudspeaker (91,93), mounted on this base (9). Electronic piano according to Claim 11, characterized in that it comprises a single loudspeaker, mounted on an internal surface on one side of the said base (9), the internal face opposite to the said loudspeaker presenting a flat surface, so as to so that the sound waves emitted by the membrane of said loudspeaker can be returned by said flat surface. Electronic piano according to any one of Claims 4 to 12, characterized in that the said box (1) is formed by at least one covering element which is in contact with a wall of the said rear chamber (42).