EP0007569A1 - Loudspeaker box - Google Patents

Abstract

1. Box speaker with the front face carrying several speakers, each speaker opening onto an internal compartment of the speaker, said compartments communicating with one another, characterized in as much as the said front face is shaped like a convex pyramid (14) at the top of which there is an H.F. loudspeaker (10), one medium-bass speaker (9) being mounted on each of the four sloping sides of the pyramid, with diagonal internal enclosures (1), projecting on the front face of the speaker, forming said internal compartments, of triangular section, and being provided with side openings (3) to allow a circular communication between the four compartments, each compartment being provided internally in the corners with means forming two tunnels (6) to send on one side some back waves created by the associated loudspeaker (9) towards two cut outs (2) formed in the corners of the front face of the compartment, the back waves being also directed towards a cut out (7) formed in the central part of the rear panel, the latter comprising a crossed divider (8) separating the cut outs (7) of the various compartments from on another, each compartment comprising one damping plate in polyester foam (4) inserted between the walls of the compartments and designed so as to allow free passage of waves towards the cut outs (2 and 7).

Description

This Invention relates to a New Sound Reproduction System, which employs on the front face a coaxial mounting of four strike-medium speakers, inclined at 2I ° placed symmetrically all around on a shape of a convex pyramid to which the central point (the axis) includes a fifth speaker for high frequencies whose dome and reflector in granular finish are treated with paraffin (see fig.I). This set has a very large dispersion thanks to a central acoustic divider in the form of two superimposed pyramid trunks, of which that of the smaller end is made of glass or granulated crystal, while the other trunk is covered with granulated carbide (see fig. 2.5.). In addition there is first the internal anti-resonant process by action and reaction and the separation system in four triangular divisions from the four corners of a rectangular shape which consists of the use of four panels which connect the four inner corners towards the center passing outside before where their edge forms a crossed division between the four loudspeakers (see fig. II), while inside they form four partitions in the form of irregular pyramids, of which two of them necessarily have dimensions and volumes unequal to the others, therefore their resonance is different.

The choice of loudspeakers with different resonance as well as the use of different absorbent materials etc ... further reinforces this effect., Then the communication by four openings (see fig.2.3) result that each speaker prevents the other from extending its own resonance, thus the audible resonance is suppressed.

The system for adjusting the interior sound pressure with recovery consists of each compartment being divided by a rectangular polyester foam plate provided with two openings towards the corners at the end (see fig. 1.4). The two outward corners of each compartment are transformed into two triangular tunnels (see fig.1.6), which return part of the sound pressure towards the two openings placed in the two front corners (see fig.1.2), while- that the other part of the sound pressure will reinforce the rearward repair by an opening at the end of each compartment which is placed in the center of the rear panel and separated from the other three openings by a crossed divider (see fig.3.7 and 8).

the rear panel as well as the four faces of the front convex pyramid, plus the four cones are of a granulated structure and covered with a mixture of pure bitumen-aluminum-carbon and asbestos, while the central domes (in bakelite ) of the four speakers are treated with a granulated pure carbon finish.

Despite intense research and promising specifications, the speaker remained the weakest link in a Hi-Fi system. This invention aims to make a fundamentally valid design, first by a concentric inclined location, in same time in all directions to avoid any musical confusion while respecting the balance between direct and reflected sound; with a specific natural transparency and timbre and without listening fatigue, as well as its total absence of audible resonance

The advantages of this invention compared with the usual technique - they are multiple and exclusive, there is the inclined orientation of the four speakers partially forward and at the same time up, down, left and right, with a beamed out from the four front corners as well as from the rear reflection, in addition the tweeter with its central location and its wide dispersion divider projects the high-pitched sound on the four inclined panels and speakers, which mix and reflect the different sounds also in all directions. Thus the propagation of symmetrical sounds both in all directions gives a truly spatial sound image, but with an extraordinary definition which avoids any confusion.

These advantages combined with a set of new emitting and reflecting materials which help to keep transparency, make the timbre specific as well as the musical character without the slightest fatigue of listening.

Finally let us add to this invention the advantages of listening without audible resonance, no trailing of a cone, relatively low volume, of a yield and a very large power without spikes, with a very wide and regular frequency range, not of thermal concentration and very interesting manufacturing price.

Claims (9)

I. For any acoustic system with coaxial mounting inclined between 0 and 90 ° of several passive speakers or radiators of all kinds, placed symmetrically all around on any shape of pyramid or spherical convex of all kinds with the adaptation of '' one or more even inclined speakers of all possible kinds, with central location by representing the axis by forming a whole. 2.For any anti-resonant acoustic system by action and reaction with communication between the set of several speakers with compartments of all shapes and combined with different dimensions, shapes, volumes and materials, forming a set. connects to a mounting at the same time several speakers of all kinds and different characteristics. 3.For any acoustic system with acoustic divider or reflector which uses one of the different kinds of granular carbide, as emitters or intermediaries of sound reflection. 4. As well as for the whole of a central divider in the form of two trunk of pyramid superimposed, which joins at the same time the glass or the crystal in granulated finish whose front face is frosted, with) a carbide finish, finish or on a granulated structure on the other trunk. 5.For application in acoustics on all surfaces capable of emitting or reflecting sound, of a mixture of natural or artificial bitumen composition with aluminum, carbon and asbestos in all proportions and different quantities, as well as for the combination of the application of this finishing mixture or on a granulated structure of all kinds and sizes forming a whole. 6.For the application of paraffin or other hydrocarbon on all domes, membranes or other reflecting or emitting surfaces, or in combination with a finish or on a granulated structure. 7.For the application of pure carbon in all forms on central bakelite or fabric domes forming a whole. 8.For the air adjustment system with rearward reflection and by rectangular tunnels formed by the corners. 9. As well as for all of all the models (see fig. 1-2 + 3.) Internally or externally with all their forms, devices, accessories and geometrical locations and this in all kinds of materials and possible dimensions obtained by casting or any other process. Deposited in Brussels, June 29, 1979.

Images