Abstract
A loudspeaker assembly enabled with means to control the directivity of sound emitted from the loudspeaker and the use of such an assembly in audio rendering equipment. The inventive assembly includes an acoustic lens having movable mechanical means enabling controlled directivity of the sound emitted from the loudspeaker by moving one or more of the movable mechanical means from a first position to a second position.
Claims
1. A loudspeaker assembly comprising: an acoustic lens having one or more movable members, where said movable members may be moved from a first position where the movable members have a first influence on a directivity of the acoustic lens, to a second position where the movable members have a second influence on the directivity of the acoustic lens, and said movable members being movable in any position in-between said first position and said second position; and a sound transducer arranged adjacent the acoustic lens for emitting sound in a first direction, and where the movable members rotate around one or more first axes parallel to the first direction.
2. The loudspeaker assembly according to claim 1, wherein: the movable members have a front surface having an extent in a direction of the one or more first axes and an extent in a direction radially to the one or more first axes, and where a movable member of said one or more movable members arranged in a radial direction to the one or more first axes has a curved shape.
3. The loudspeaker assembly according to claim 2 wherein: the curved shape is convex, as seen from a listening position.
4. The loudspeaker assembly according to claim 1, wherein: the movable members are moved by electromechanical means.
5. The loudspeaker assembly according to claim 1, further including: one or more low range transducers; one or more midrange transducers; at least one acoustic lens with a high range transducer; and wherein signals delivered from a first amplifier to each of the one or more low range transducers, the one or more midrange transducers, and the at least one acoustic lens and sound transducer, is passed through a finite impulse response filter and through an infinite impulse response filter for each of the one or more low range transducers, one or more midrange transducers, and the at least one acoustic lens and sound transducer.
6. The loudspeaker assembly according to claim 5 wherein: the signals after having passed through the finite impulse response filter and the infinite impulse response filter for each of the one or more low range transducers, one or more midrange transducers, and the at least one acoustic lens with sound transducer is sent to a separate second power amplifier connected to each of the one or more low range transducers, the one or more midrange transducers, and the at least one acoustic lens with sound transducer.
7. The loudspeaker assembly according to claim 5 wherein the assembly includes two acoustic lenses, where a first acoustic lens is provided for higher frequencies corresponding to treble and a second acoustic lens is provided for mid-tone frequencies.
8. The loudspeaker assembly according to claim 1 wherein: the one or more movable members include two movable members, and where the two movable members move symmetrically or asymmetrically around their respective axis of the one or more first axes.
9. The loudspeaker assembly according to claim 1 wherein: the loudspeaker assembly is arranged in a housing, and where the acoustic lens is retractable into the housing.
10. The loudspeaker assembly according to claim 1 wherein: the acoustic lens is provided with light emitting means that may be controlled to emit different colored light and/or different light intensity corresponding to a status of the loudspeaker assembly.
Description
(1) The invention will now be described with reference to the accompanying drawings, in which:
(2) FIG. 1 illustrates a loudspeaker assembly including an acoustic lens.
(3) FIGS. 2 & 3 illustrate a loudspeaker assembly with the acoustic lens exposed.
(4) FIGS. 4 & 5 illustrate alternative positions of an acoustic lens.
(5) FIG. 6a illustrates an example of the movable members of the acoustic lens.
(6) FIG. 6b illustrates a view of an acoustic lens where the top of the lens has been removed.
(7) FIG. 7 illustrates a side view of an embodiment of the acoustic lens.
(8) FIG. 8a illustrates alternative positions of the movable members according to acoustic lens configurations.
(9) FIG. 8b illustrates a top view of optional geometrical shapes of the movable members.
(10) FIG. 9 illustrates sound fields related to wide and narrow modes of directivity.
(11) FIG. 10 illustrates the controlled horizontal dispersion of the sound energy as a function of frequency.
(12) FIG. 11 illustrates a block diagram of a loudspeaker assembly.
DETAILED DESCRIPTION OF THE INVENTION
(13) FIG. 1 displays a loudspeaker assembly (2) according to the invention, where the assembly includes a tweeter built into an acoustic lens, and where the acoustic lens upper surface (1) is retracted into the surface of the loudspeaker assembly (2) and seamlessly integrates with the upper surface of loudspeaker assembly (2). FIG. 2 illustrates the acoustic lens (1), in an intermediate position during movement from a closed (non-exposed) position to an open position in which part of the sound transducer/tweeter (8) is visible. Sidewalls (3) of the acoustic lens are partly visible.
(14) FIG. 3 illustrates the acoustic lens (1), in an open (exposed) position in which the tweeter (8) is visible. Sidewalls (3) of the acoustic lens are partly exposed. Part of the bottom plate (4) of the acoustic lens and a lower part (9) of the top plate (1) define a gap enabled to control the dispersion of sound emitted out from the acoustic lens, particularly vertically. The tweeter's direction of sound emission is illustrated by the dashed axis (40).
(15) In FIGS. 3, 4 and 5, the acoustic lens is enabled with movable members (5, 5, 6, 6, 7, 7) where in a first position (5,5) a first mode with wide directivity is enabled and in a second exposed position (6,6) a second mode with a narrower directivity is enabled and in a third mode with an exposed position (7,7) a furthermore narrower directivity is enabled. For illustration purposes only, the means for bringing the acoustic lens according to the present invention from its first to its second and third modes/positions are not depicted, as any suitable means for providing the movement may be applied.
(16) FIG. 6a displays an embodiment of the electromechanical means enabled for moving the movable members (61,62) that control the horizontal directivity of the distributed sound coming from the tweeter (8). The means include at least one motor (63), and combinations of tooth wheels (65) and/or friction wheels (67) and/or drive wheels (66) engaging with means (64) that connects to the movable members (5,5 & 6,6 & 7,7). Hinge means (68) connects to the two members (61,62) and enables the rotation around a common axis (60), of said members. In the illustrated embodiment, a symmetrical (coupled) movement of the movable members (61,62) is achieved, e.g. such that the emitted sound will be emitted symmetrically (horizontally in use). However, it is also possible to construct a movement mechanism creating an asymmetrical (independent) movement of the two movable members (61,62). This may for example be by coupling each of the movable members to separate actuators, step-motors or the like.
(17) In FIG. 6b is illustrated a view of an acoustic lens (1) according to the invention, where the top of the lens has been removed. The tweeter (8) is arranged substantially centrally in the lens (1), and the center axis (60) for rotation of the movable members (5,5) as illustrated in FIG. 6a is coinciding with the center axis (40) of the tweeter (8). As the movable members (5,5) are moved from their widest positiona position where the stops (45,45) are engaging the rear cover (44) at corresponding stops (46,46) into a position as illustrated the opening behind the convex surfaces (5,5) are covered by curved walls (43,43). In this manner the acoustic lens, regardless of its directivity angle, i.e. the relative angle between the movable members and thereby the curved surfaces (5,5), will always have a full outer surface because of the provision of the back cover (44), the curved walls, (43,43) and the convex surfaces (5,5).
(18) FIG. 7 displays a perspective side view of the acoustic lens arrangement (1), with the top plate (9), the fixed side walls (3), the bottom plate (4), the movable members (5, 5) and the tweeter (8).
(19) When constructing the movable acoustic lens, it is important to avoid wide gaps between the movable members and the top and bottom plates of the acoustic lens. Such wide gaps would lead to distortion of the sound. Furthermore, any cavities behind the movable members must be filled with sound absorbing material to avoid distortion of the sound due to any residual leakage of sound energy leaking through the remaining gaps.
(20) FIG. 8.a displays a top view of the acoustic lens with illustrations of the modes of directivity and related positions of the movable members (5,5). The movable members (5,5) have center of rotation on a common axis (60) as illustrated in FIG. 6a. According to functional and/or industrial design requirements said center axis of rotation may be the same as the center axis (40) of the tweeter (8) or a center axis (40) offset and on a perpendicular line through the tweeter center (40).
(21) The wide mode of directivity is (10, 10) with the movable members (5,5) in a closed position (first position).
(22) The narrow mode of directivity is (20, 20) with the movable members (5,5) in an open position (second position).
(23) In this connection open and closed positions refer to how exposed the movable members are. When the movable members are in their first position, they interfere the least with the emitted sound and vice-versa.
(24) An intermediate mode of directivity is (30, 30) with the movable members (5,5) in a partly open position (third position). This represents a position during movement from first to second position. Optionally this mode is applied as a medium narrow mode of operation, delivering a medium narrow directivity. Anyway, any position of the movable members (5,5) between the most wide position (10,10) and the most narrow position (20,20) may be used. Also, any asymmetrical combination of relative positions between the movable members (5,5) may be used. This is particularly interesting in case the horizontal directivity is controlled and utilized. For example, one movable member (5) may be in position (10) while the other movable member (5) is in position (20). In this configuration the acoustic lens will direct its sound emission towards the right (seen from the listener's position) as seen in FIG. 8a.
(25) FIG. 8.b illustrates a top view of optional geometrical shapes of the movable members (5,5). In one embodiment (11), a straight line defines the borderline. In an alternative embodiment (12) a curved line defines the borderline. Said curved lines being straight lines with starting points at center point (40) and the curved part of the lines having end points (10 and 10) at the periphery of the circle that includes the acoustic lens. The exact shape of the curved line can be complex and is determined by careful design, simulations and measurements with the goal of optimising the acoustic characteristics of the acoustic lens avoiding any unwanted effect on the sound reproduction.
(26) FIG. 9 displays examples of sound radiation patterns representing the two modes of directivity operation being narrow (92) or wide (91) and with horizontal dispersion.
(27) The illustration displays the sound radiation patterns as polar diagrams. The two polar diagrams have been normalized for the 0-degree direction. The polar area (25) corresponds to the narrow position (corresponding to 20,20see FIG. 8a) of the movable members (5,5), whereas the polar area (26) illustrate the widest position (corresponding to (10,10)see FIG. 8a) of the movable members.
(28) FIG. 10 displays an example of the horizontal dispersion of sound emitted from the loudspeaker assembly that includes the acoustic lens according to the invention. The effect of the controlled directivity from the tweeter and the acoustic lens as an assembly is effective in the frequency range (95) from 4 kHz and above. The directivity in the low range frequencies (93) is controlled by the multiple low range loudspeaker transducers in combination with the appropriate filter settings. The directivity in the midrange frequencies (94) can be controlled by the multiple midrange loudspeaker transducers in combination with the appropriate filter settings or with an acoustic lens combined with a single midrange loudspeaker transducer.
(29) In the embodiment of the invention disclosed in FIG. 11, the idea is to combine mechanical movement of the movable members of the acoustic lens with DSP control in order to control the sound dispersion of the total system.
(30) The system 100 consists of three low range transducers (101,102,103) (woofers), three midrange transducers (104,105,106), and a tweeter (8) mounted in a mechanical reflectoracoustic lens (9), that is able to change its shape, as explained above. In the figure, the acoustic lens (9) is illustrated in two different modes, a wide mode (91) and a narrow mode (92). These modes correspond to the positions of the movable members (5,5) as explained above with reference to for example FIG. 8a. The input signal (110) is filtered by FIR (Finite Impulse Response) and IIR (Infinite Impulse Response) filters before it is sent to separate power amplifiers 111-111, connected to each transducer. The signal flow is shown in FIG. 11.
(31) The system (100) gives the opportunity to change the directivity of the speaker assembly (100) at all frequencies. A mechanical movement that changes the shape of the acoustic lens (9) controls the tweeter directivity, see for example the radiation patterns in FIG. 9. In order to adapt the directivity of the woofers (101,102,103) and midrange transducers (104,105,106), the FIR and IIR filter coefficients are changed simultaneously such that the directivity of all sections (woofer, midrange and tweeter) match. The tweeter FIR and IIR filters are changed likewise such that the frequency responses of all sections align and sum up to the desired frequency response.
(32) The narrow directivity target has a dispersion of for example +/45 and the wide directivity target has a dispersion of for example +/90 at a sound level of for example 3 dB compared to the on-axis sound level (0 dB). In FIG. 8a the accumulated directivity target, directivity angle is illustrated as the arc (15). Each mechanical angle has a corresponding filter set (see the table below) which matches the directivity of the tweeter in that specific angle.
(33) It is of interest that the directivity is constant across frequencies. However, it is important that the directivity does not widen at higher frequencies. Therefore, the resulting directivity of the midranges should not be narrower than the tweeter directivity.
(34) Generally seen the woofer section (101,102,103) operates below 400 Hz, the midrange (104,105,106) between 400 Hz and 4000 Hz, and the tweeter (8) above 4000 Hz. However, the frequency ranges are changeable to utilise the natural directivity of the drivers as much as possible.
(35) The orders of the filters are not fixed. They depend on the physical realisation of the system, the precision demand, and the sampling rate.
(36) In table 1 is illustrated the filter coefficients for two mechanical lens shapes. LFIRx denotes the FIR filter length of FIR filter x and LIIRy denotes the number of biquads in IIR filter y.
(37) TABLE-US-00001 TabIe 1 Filter Narrow directivity Wide directivity FIR1 a.sub.FIR1.sub..sub.N.sub..sub.0, a.sub.FIR1.sub..sub.N.sub..sub.1, . . . , a.sub.FIR.sub..sub.1.sub..sub.N.sub..sub.LFIR1 a.sub.FIR1.sub..sub.W.sub..sub.0, a.sub.FIR1.sub..sub.W.sub..sub.1, . . . , a.sub.FIR1.sub..sub.W.sub..sub.LFIR1 IIR1 b.sub.IIR1.sub..sub.N.sub..sub.1.sub..sub.0, b.sub.IIR1.sub..sub.N.sub..sub.1.sub..sub.1, b.sub.IIR1.sub..sub.N.sub..sub.1.sub..sub.2, b.sub.IIR1.sub..sub.W.sub..sub.1.sub..sub.0, b.sub.IIR1.sub..sub.W.sub..sub.1.sub..sub.1, b.sub.IIR1.sub..sub.W.sub..sub.1.sub..sub.2, a.sub.IIR1.sub..sub.N.sub..sub.1.sub..sub.1, a.sub.IIR1.sub..sub.N.sub..sub.1.sub..sub.2 a.sub.IIR1.sub..sub.W.sub..sub.1.sub..sub.1, a.sub.IIR1.sub..sub.W.sub..sub.1.sub..sub.2 b.sub.IIR1.sub..sub.N.sub..sub.2.sub..sub.0, b.sub.IIR1.sub..sub.N.sub..sub.2.sub..sub.1, b.sub.IIR1.sub..sub.N.sub..sub.2.sub..sub.2, b.sub.IIR1.sub..sub.W.sub..sub.2.sub..sub.0, b.sub.IIR1.sub..sub.W.sub..sub.2.sub..sub.1, b.sub.IIR1.sub..sub.W.sub..sub.2.sub..sub.2, a.sub.IIR1.sub..sub.N.sub..sub.2.sub..sub.1, a.sub.IIR1.sub..sub.N.sub..sub.2.sub..sub.2 a.sub.IIR1.sub..sub.W.sub..sub.2.sub..sub.1, a.sub.IIR1.sub..sub.W.sub..sub.2.sub..sub.2 . . . . . . b.sub.IIR1.sub..sub.N.sub..sub.LIIR1.sub..sub.0, b.sub.IIR1.sub..sub.N.sub..sub.LIIR1.sub..sub.1, b.sub.IIR1.sub..sub.N.sub..sub.L.sub..sub.2, b.sub.IIR1.sub..sub.W.sub..sub.LIIR1.sub..sub.0, b.sub.IIR1.sub..sub.W.sub..sub.LIIR1.sub..sub.1, b.sub.IIR1.sub..sub.W.sub..sub.L.sub..sub.2, a.sub.IIR1.sub..sub.N.sub..sub.LIIR1.sub..sub.1, a.sub.IIR1.sub..sub.N.sub..sub.LIIR1.sub..sub.2 a.sub.IIR1.sub..sub.W.sub..sub.LIIR1.sub..sub.1, a.sub.IIR1.sub..sub.W.sub..sub.LIIR1.sub..sub.2 FIR2 a.sub.FIR2.sub..sub.N.sub..sub.0, a.sub.FIR2.sub..sub.N.sub..sub.1, . . . , a.sub.IIR2.sub..sub.N.sub..sub.LFIR2 a.sub.FIR2.sub..sub.W.sub..sub.0, a.sub.FIR2.sub..sub.W.sub..sub.1, . . . , a.sub.FIR2.sub..sub.W.sub..sub.LFIR2 IIR2 b.sub.IIR2.sub..sub.N.sub..sub.1.sub..sub.0, b.sub.IIR2.sub..sub.N.sub..sub.1.sub..sub.1, b.sub.IIR2.sub..sub.N.sub..sub.1.sub..sub.2, b.sub.IIR2.sub..sub.W.sub..sub.1.sub..sub.0, b.sub.IIR2.sub..sub.W.sub..sub.1.sub..sub.1, b.sub.IIR2.sub..sub.W.sub..sub.1.sub..sub.2, a.sub.IIR2.sub..sub.N.sub..sub.1.sub..sub.1, a.sub.IIR2.sub..sub.N.sub..sub.1.sub..sub.2 a.sub.IIR2.sub..sub.W.sub..sub.1.sub..sub.1, a.sub.IIR2.sub..sub.W.sub..sub.1.sub..sub.2 b.sub.IIR2.sub..sub.N.sub..sub.2.sub..sub.0, b.sub.IIR2.sub..sub.N.sub..sub.2.sub..sub.1, b.sub.IIR2.sub..sub.N.sub..sub.2.sub..sub.2, b.sub.IIR2.sub..sub.W.sub..sub.2.sub..sub.0, b.sub.IIR2.sub..sub.W.sub..sub.2.sub..sub.1, b.sub.IIR2.sub..sub.W.sub..sub.2.sub..sub.2, a.sub.IIR2.sub..sub.N.sub..sub.2.sub..sub.1, a.sub.IIR2.sub..sub.N.sub..sub.2.sub..sub.2 a.sub.IIR2.sub..sub.W.sub..sub.2.sub..sub.1, a.sub.IIR2.sub..sub.W.sub..sub.2.sub..sub.2 . . . . . . b.sub.IIR2.sub..sub.N.sub..sub.LIIR2.sub..sub.0, b.sub.IIR2.sub..sub.N.sub..sub.LIIR2.sub..sub.1, b.sub.IIR2.sub..sub.N.sub..sub.L.sub..sub.2, b.sub.IIR2.sub..sub.W.sub..sub.LIIR2.sub..sub.0, b.sub.IIR2.sub..sub.W.sub..sub.LIIR2.sub..sub.1, b.sub.IIR2.sub..sub.W.sub..sub.L.sub..sub.2, a.sub.IIR2.sub..sub.N.sub..sub.LIIR2.sub..sub.1, a.sub.IIR2.sub..sub.N.sub..sub.LIIR2.sub..sub.2 a.sub.IIR2.sub..sub.W.sub..sub.LIIR2.sub..sub.1, a.sub.IIR2.sub..sub.W.sub..sub.LIIR2.sub..sub.2 FIR3 a.sub.FIR3.sub..sub.N.sub..sub.0, a.sub.FIR3.sub..sub.N.sub..sub.1, . . . , a.sub.FIR3.sub..sub.N.sub..sub.LFIR3 a.sub.FIR3.sub..sub.W.sub..sub.0, a.sub.FIR3.sub..sub.W.sub..sub.1, . . . , a.sub.FIR3.sub..sub.W.sub..sub.LFIR3 IIR3 b.sub.IIR3.sub..sub.N.sub..sub.1.sub..sub.0, b.sub.IIR3.sub..sub.N.sub..sub.1.sub..sub.1, b.sub.IIR3.sub..sub.N.sub..sub.1.sub..sub.2, b.sub.IIR3.sub..sub.W.sub..sub.1.sub..sub.0, b.sub.IIR3.sub..sub.W.sub..sub.1.sub..sub.1, b.sub.IIR3.sub..sub.W.sub..sub.1.sub..sub.2, a.sub.IIR3.sub..sub.N.sub..sub.1.sub..sub.1, a.sub.IIR3.sub..sub.N.sub..sub.1.sub..sub.2 a.sub.IIR3.sub..sub.W.sub..sub.1.sub..sub.1, a.sub.IIR3.sub..sub.W.sub..sub.1.sub..sub.2 b.sub.IIR3.sub..sub.N.sub..sub.2.sub..sub.0, b.sub.IIR3.sub..sub.N.sub..sub.2.sub..sub.1, b.sub.IIR3.sub..sub.N.sub..sub.2.sub..sub.2, b.sub.IIR3.sub..sub.W.sub..sub.2.sub..sub.0, b.sub.IIR3.sub..sub.W.sub..sub.2.sub..sub.1, b.sub.IIR3.sub..sub.W.sub..sub.2.sub..sub.2, a.sub.IIR3.sub..sub.N.sub..sub.2.sub..sub.1, a.sub.IIR3.sub..sub.N.sub..sub.2.sub..sub.2 a.sub.IIR3.sub..sub.W.sub..sub.2.sub..sub.1, a.sub.IIR3.sub..sub.W.sub..sub.2.sub..sub.2 . . . . . . b.sub.IIR3.sub..sub.N.sub..sub.LIIR3.sub..sub.0, b.sub.IIR3.sub..sub.N.sub..sub.LIIR3.sub..sub.1, b.sub.IIR3.sub..sub.N.sub..sub.L.sub..sub.2, b.sub.IIR3.sub..sub.W.sub..sub.LIIR3.sub..sub.0, b.sub.IIR3.sub..sub.W.sub..sub.LIIR3.sub..sub.1, b.sub.IIR3.sub..sub.W.sub..sub.L.sub..sub.2, a.sub.IIR3.sub..sub.N.sub..sub.LIIR3.sub..sub.1, a.sub.IIR3.sub..sub.N.sub..sub.LIIR3.sub..sub.2 a.sub.IIR3.sub..sub.W.sub..sub.LIIR3.sub..sub.1, a.sub.IIR3.sub..sub.W.sub..sub.LIIR3.sub..sub.2 FIR4 a.sub.FIR4.sub..sub.N.sub..sub.0, a.sub.FIR4.sub..sub.N.sub..sub.1, . . . , a.sub.FIR4.sub..sub.N.sub..sub.LFIR4 a.sub.FIR4.sub..sub.W.sub..sub.0, a.sub.FIR4.sub..sub.W.sub..sub.1, . . . , a.sub.FIR4.sub..sub.W.sub..sub.LFIR4 IIR4 b.sub.IIR4.sub..sub.N.sub..sub.1.sub..sub.0, b.sub.IIR4.sub..sub.N.sub..sub.1.sub..sub.1, b.sub.IIR4.sub..sub.N.sub..sub.1.sub..sub.2, b.sub.IIR4.sub..sub.W.sub..sub.1.sub..sub.0, b.sub.IIR4.sub..sub.W.sub..sub.1.sub..sub.1, b.sub.IIR4.sub..sub.W.sub..sub.1.sub..sub.2, a.sub.IIR4.sub..sub.N.sub..sub.1.sub..sub.1, a.sub.IIR4.sub..sub.N.sub..sub.1.sub..sub.2 a.sub.IIR4.sub..sub.W.sub..sub.1.sub..sub.1, a.sub.IIR4.sub..sub.W.sub..sub.1.sub..sub.2 b.sub.IIR4.sub..sub.N.sub..sub.2.sub..sub.0, b.sub.IIR4.sub..sub.N.sub..sub.2.sub..sub.1, b.sub.IIR4.sub..sub.N.sub..sub.2.sub..sub.2, b.sub.IIR4.sub..sub.W.sub..sub.2.sub..sub.0, b.sub.IIR4.sub..sub.W.sub..sub.2.sub..sub.1, b.sub.IIR4.sub..sub.W.sub..sub.2.sub..sub.2, a.sub.IIR4.sub..sub.N.sub..sub.2.sub..sub.1, a.sub.IIR4.sub..sub.N.sub..sub.2.sub..sub.2 a.sub.IIR4.sub..sub.W.sub..sub.2.sub..sub.1, a.sub.IIR4.sub..sub.W.sub..sub.2.sub..sub.2 . . . . . . b.sub.IIR4.sub..sub.N.sub..sub.LIIR4.sub..sub.0, b.sub.IIR4.sub..sub.N.sub..sub.LIIR4.sub..sub.1, b.sub.IIR4.sub..sub.N.sub..sub.L.sub..sub.2, b.sub.IIR4.sub..sub.W.sub..sub.LIIR4.sub..sub.0, b.sub.IIR4.sub..sub.W.sub..sub.LIIR4.sub..sub.1, b.sub.IIR4.sub..sub.W.sub..sub.L.sub..sub.2, a.sub.IIR4.sub..sub.N.sub..sub.LIIR4.sub..sub.1, a.sub.IIR4.sub..sub.N.sub..sub.LIIR4.sub..sub.2 a.sub.IIR4.sub..sub.W.sub..sub.LIIR4.sub..sub.1, a.sub.IIR4.sub..sub.W.sub..sub.LIIR4.sub..sub.2 FIR5 a.sub.FIR5.sub..sub.N.sub..sub.0, a.sub.FIR5.sub..sub.N.sub..sub.1, . . . , a.sub.FIR5.sub..sub.N.sub..sub.LFIR5 a.sub.FIR5.sub..sub.W.sub..sub.0, a.sub.FIR5.sub..sub.W.sub..sub.1, . . . , a.sub.FIR5.sub..sub.W.sub..sub.LFIR5 IIR5 b.sub.IIR5.sub..sub.N.sub..sub.1.sub..sub.0, b.sub.IIR5.sub..sub.N.sub..sub.1.sub..sub.1, b.sub.IIR5.sub..sub.N.sub..sub.1.sub..sub.2, b.sub.IIR5.sub..sub.W.sub..sub.1.sub..sub.0, b.sub.IIR5.sub..sub.W.sub..sub.1.sub..sub.1, b.sub.IIR5.sub..sub.W.sub..sub.1.sub..sub.2, a.sub.IIR5.sub..sub.N.sub..sub.1.sub..sub.1, a.sub.IIR5.sub..sub.N.sub..sub.1.sub..sub.2 a.sub.IIR5.sub..sub.W.sub..sub.1.sub..sub.1, a.sub.IIR5.sub..sub.W.sub..sub.1.sub..sub.2 b.sub.IIR5.sub..sub.N.sub..sub.2.sub..sub.0, b.sub.IIR5.sub..sub.N.sub..sub.2.sub..sub.1, b.sub.IIR5.sub..sub.N.sub..sub.2.sub..sub.2, b.sub.IIR5.sub..sub.W.sub..sub.2.sub..sub.0, b.sub.IIR5.sub..sub.W.sub..sub.2.sub..sub.1, b.sub.IIR5.sub..sub.W.sub..sub.2.sub..sub.2, a.sub.IIR5.sub..sub.N.sub..sub.2.sub..sub.1, a.sub.IIR5.sub..sub.N.sub..sub.2.sub..sub.2 a.sub.IIR5.sub..sub.W.sub..sub.2.sub..sub.1, a.sub.IIR5.sub..sub.W.sub..sub.2.sub..sub.2 . . . . . . b.sub.IIR5.sub..sub.N.sub..sub.LIIR5.sub..sub.0, b.sub.IIR5.sub..sub.N.sub..sub.LIIR5.sub..sub.1, b.sub.IIR5.sub..sub.N.sub..sub.L.sub..sub.2, b.sub.IIR5.sub..sub.W.sub..sub.LIIR5.sub..sub.0, b.sub.IIR5.sub..sub.W.sub..sub.LIIR5.sub..sub.1, b.sub.IIR5.sub..sub.W.sub..sub.L.sub..sub.2, a.sub.IIR5.sub..sub.N.sub..sub.LIIR5.sub..sub.1, a.sub.IIR5.sub..sub.N.sub..sub.LIIR5.sub..sub.2 a.sub.IIR5.sub..sub.W.sub..sub.LIIR5.sub..sub.1, a.sub.IIR5.sub..sub.W.sub..sub.LIIR5.sub..sub.2 FIR6 a.sub.FIR6.sub..sub.N.sub..sub.0, a.sub.FIR6.sub..sub.N.sub..sub.1, . . . , a.sub.IIR6.sub..sub.N.sub..sub.LFIR6 a.sub.FIR6.sub..sub.W.sub..sub.0, a.sub.FIR6.sub..sub.W.sub..sub.1, . . . , a.sub.FIR6.sub..sub.W.sub..sub.LFIR6 IIR6 b.sub.IIR6.sub..sub.N.sub..sub.1.sub..sub.0, b.sub.IIR6.sub..sub.N.sub..sub.1.sub..sub.1, b.sub.IIR6.sub..sub.N.sub..sub.1.sub..sub.2, b.sub.IIR6.sub..sub.W.sub..sub.1.sub..sub.0, b.sub.IIR6.sub..sub.W.sub..sub.1.sub..sub.1, b.sub.IIR6.sub..sub.W.sub..sub.1.sub..sub.2, a.sub.IIR6.sub..sub.N.sub..sub.1.sub..sub.1, a.sub.IIR6.sub..sub.N.sub..sub.1.sub..sub.2 a.sub.IIR6.sub..sub.W.sub..sub.1.sub..sub.1, a.sub.IIR6.sub..sub.W.sub..sub.1.sub..sub.2 b.sub.IIR6.sub..sub.N.sub..sub.2.sub..sub.0, b.sub.IIR6.sub..sub.N.sub..sub.2.sub..sub.1, b.sub.IIR6.sub..sub.N.sub..sub.2.sub..sub.2, b.sub.IIR6.sub..sub.W.sub..sub.2.sub..sub.0, b.sub.IIR6.sub..sub.W.sub..sub.2.sub..sub.1, b.sub.IIR6.sub..sub.W.sub..sub.2.sub..sub.2, a.sub.IIR6.sub..sub.N.sub..sub.2.sub..sub.1, a.sub.IIR6.sub..sub.N.sub..sub.2.sub..sub.2 a.sub.IIR6.sub..sub.W.sub..sub.2.sub..sub.1, a.sub.IIR6.sub..sub.W.sub..sub.2.sub..sub.2 . . . . . . b.sub.IIR6.sub..sub.N.sub..sub.LIIR6.sub..sub.0, b.sub.IIR6.sub..sub.N.sub..sub.LIIR6.sub..sub.1, b.sub.IIR6.sub..sub.N.sub..sub.L.sub..sub.2, b.sub.IIR6.sub..sub.W.sub..sub.LIIR6.sub..sub.0, b.sub.IIR6.sub..sub.W.sub..sub.LIIR6.sub..sub.1, b.sub.IIR6.sub..sub.W.sub..sub.L.sub..sub.2, a.sub.IIR6.sub..sub.N.sub..sub.LIIR6.sub..sub.1, a.sub.IIR6.sub..sub.N.sub..sub.LIIR6.sub..sub.2 a.sub.IIR6.sub..sub.W.sub..sub.LIIR6.sub..sub.1, a.sub.IIR6.sub..sub.W.sub..sub.LIIR6.sub..sub.2 FIR7 a.sub.FIR7.sub..sub.N.sub..sub.0, a.sub.FIR7.sub..sub.N.sub..sub.1, . . . , a.sub.FIR7.sub..sub.N.sub..sub.LFIR7 a.sub.FIR7.sub..sub.W.sub..sub.0, a.sub.FIR7.sub..sub.W.sub..sub.1, . . . , a.sub.FIR7.sub..sub.W.sub..sub.LFIR7 IIR7 b.sub.IIR7.sub..sub.N.sub..sub.1.sub..sub.0, b.sub.IIR7.sub..sub.N.sub..sub.1.sub..sub.1, b.sub.IIR7.sub..sub.N.sub..sub.1.sub..sub.2, b.sub.IIR7.sub..sub.W.sub..sub.1.sub..sub.0, b.sub.IIR7.sub..sub.W.sub..sub.1.sub..sub.1, b.sub.IIR7.sub..sub.W.sub..sub.1.sub..sub.2, a.sub.IIR7.sub..sub.N.sub..sub.1.sub..sub.1, a.sub.IIR7.sub..sub.N.sub..sub.1.sub..sub.2 a.sub.IIR7.sub..sub.W.sub..sub.1.sub..sub.1, a.sub.IIR7.sub..sub.W.sub..sub.1.sub..sub.2 b.sub.IIR7.sub..sub.N.sub..sub.2.sub..sub.0, b.sub.IIR7.sub..sub.N.sub..sub.2.sub..sub.1, b.sub.IIR7.sub..sub.N.sub..sub.2.sub..sub.2, b.sub.IIR7.sub..sub.W.sub..sub.2.sub..sub.0, b.sub.IIR7.sub..sub.W.sub..sub.2.sub..sub.1, b.sub.IIR7.sub..sub.W.sub..sub.2.sub..sub.2, a.sub.IIR7.sub..sub.N.sub..sub.2.sub..sub.1, a.sub.IIR7.sub..sub.N.sub..sub.2.sub..sub.2 a.sub.IIR7.sub..sub.W.sub..sub.2.sub..sub.1, a.sub.IIR7.sub..sub.W.sub..sub.2.sub..sub.2 . . . . . . b.sub.IIR7.sub..sub.N.sub..sub.LIIR7.sub..sub.0, b.sub.IIR7.sub..sub.N.sub..sub.LIIR7.sub..sub.1, b.sub.IIR7.sub..sub.N.sub..sub.L.sub..sub.2, b.sub.IIR7.sub..sub.W.sub..sub.LIIR7.sub..sub.0, b.sub.IIR7.sub..sub.W.sub..sub.LIIR7.sub..sub.1, b.sub.IIR7.sub..sub.W.sub..sub.L.sub..sub.2, a.sub.IIR7.sub..sub.N.sub..sub.LIIR7.sub..sub.1, a.sub.IIR7.sub..sub.N.sub..sub.LIIR7.sub..sub.2 a.sub.IIR7.sub..sub.W.sub..sub.LIIR7.sub..sub.1, a.sub.IIR7.sub..sub.W.sub..sub.LIIR7.sub..sub.2
(38) For all the embodiments described with reference to any of the figures, the loudspeaker assembly may advantageously be equipped with an impact sensing system such that if the loudspeaker assembly detects an impact for example in the shape of a hand or other body part being placed or hit upon the loudspeaker assembly (1), it may automatically and optionally retract into the first non-exposed position or return to the second exposed position depending on the location and the nature of the impact, thereby protecting both the loudspeaker assembly according to the invention, but also the body part.
