VEHICLE LOUDSPEAKER ARRAY - European Patent Office

VEHICLE LOUDSPEAKER ARRAY - European Patent Office
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EP 1 634 479 B1
EUROPEAN PATENT SPECIFICATION
(12)
(45) Date of publication and mention
(51) Int Cl.:
H04R 1/34 (2006.01)
of the grant of the patent:
26.10.2011 Bulletin 2011/43
(86) International application number:
PCT/US2005/017795
(21) Application number: 05757209.1
(87) International publication number:
(22) Date of filing: 19.05.2005
WO 2005/115050 (01.12.2005 Gazette 2005/48)
(54) VEHICLE LOUDSPEAKER ARRAY
FAHRZEUG-LAUTSPRECHERGRUPPE
AGENCEMENT DE HAUT-PARLEURS DE VEHICULE
(84) Designated Contracting States:
(72) Inventors:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR
HU IE IS IT LI LT LU MC NL PL PT RO SE SI SK TR
(30) Priority: 19.05.2004 US 572366 P
(43) Date of publication of application:
15.03.2006 Bulletin 2006/11
(73) Proprietor: HARMAN INTERNATIONAL
EP 1 634 479 B1
INDUSTRIES, INCORPORATED
Northridge
California 91329 (US)
• HUTT, Steven, W.
Bloomington, IN 47401 (US)
• KEELE, Broadus, D. Jr.
Bloomington, IN 47408 (US)
(74) Representative: Grünecker, Kinkeldey,
Stockmair & Schwanhäusser
Leopoldstrasse 4
80802 München (DE)
(56) References cited:
EP-A- 0 481 163
US-B1- 6 584 202
GB-A- 2 273 847
Note: Within nine months of the publication of the mention of the grant of the European patent in the European Patent
Bulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with the
Implementing Regulations. Notice of opposition shall not be deemed to have been filed until the opposition fee has been
paid. (Art. 99(1) European Patent Convention).
Printed by Jouve, 75001 PARIS (FR)
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Description
BACKGROUND OF THE INVENTION
1. Technical Field.
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[0001] The invention generally relates to loudspeakers. More particularly, the invention relates to a loudspeaker array in a vehicle.
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2. Related Art.
[0002] Loudspeaker line array technology has been
used for numerous years. Typically loudspeaker line arrays are used in sound reinforcement systems. In their
simplest form, the interaction of adjacent line-array transducers modifies the total acoustic radiation characteristics of the line array. In commercial applications, the major axis of the line array is usually oriented vertically. An
example vertically oriented line array is the JBL Pro
VerTec loudspeaker arrays used in large performance
venues.
[0003] Vehicles typically include some form of audio
system having loudspeakers. Tuning and optimization of
audio systems in vehicles is usually more difficult than in
a typical room such as in a home. In a vehicle, loudspeakers must be placed where space is made available by
the vehicle manufacturer, instead of at the optimum listening location, such as the typical location of loudspeakers in a home theater system. In addition, barriers, such
as the front seats, passengers, etc., create obstructions
to the sound waves emanated from loudspeakers. Further, glass, plastic and other highly reflective surfaces as
well as seats, headliners, etc. that create sound absorptive surfaces tend to create sound fields that are less
than desirable. Reflected sound may be out of phase with
the sound waves emanating from a loudspeaker and may
cause comb filtering. In addition, absorption of the sound
may eliminate frequencies or ranges of frequencies. As
a result, the image formed by the stereo sound may be
imprecise, and/or have other less desirable characteristics.
UK 2 273 847 A discloses a loudspeaker unit for a vehicle
installed in a dashboard close to the windshield and provided with some sound mirror. A line array of loudspeakers may be provided in the dashboard.
US 6 584 202 B1 discloses a method and device for reproducing a stereophonic audio signal employing different loudspeakers. EP 0 481 163 A2 discloses a loudspeaker for use in an automobile wherein a grille is
mounted to the speaker frame so as to reflect generated
sound.
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SUMMARY
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[0004] This invention provides a loudspeaker array in
a vehicle according claim 1. The loudspeaker array may
be operated in a vehicle with an audio system that in-
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cludes the array of transducers and associated amplifier
(s) to create single, stereo, or multi-channel sound field
images for listeners positioned in the vehicle. The transducer array may be composed of a plurality of wideband
miniature loudspeakers that may be located at the intersection of a window in the vehicle, such as the windshield,
and a horizontal shelf or dashboard positioned in a vehicle, such as an instrument panel dashboard. In other
words, the array of loudspeakers may be positioned substantially at the convergence of the window and the dashboard.
[0005] The array may be driven by one or more audio
signals provided by a bank of multi-channel processorcontrolled automotive amplifiers capable of providing
separate processor/amplifier power to each loudspeaker
in the array. By being positioned to longitudinally extend
in a single line horizontally across a vehicle, the array
may provide pin-point imaging laterally across the array.
In other words, although the sound may actually be emanating from each of the loudspeakers, from a listener’s
perspective the sound is perceived to be emanating from
the loudspeaker that is located directly in front of (or behind) the listener when the array is driven with a mono
signal. Similarly, when the array is driven with a stereo
signal the pin-point imaging may be selected to be positioned anywhere on the array based on the phase/delay
and the amplitude of the emanated sound.
[0006] Due to the physical positioning of the array, and
the relatively small diameter loudspeakers included in
the array, the horizontal coverage pattern of the sound
field may effectively narrow and focus the sound field
imaging. In addition the vertical coverage pattern may be
widened; however the image perceived by a listener may
be narrowed due to the position of the array with respect
to the reflective surface. Since a passenger in a vehicle
will be within the near field of the loudspeaker array, the
sharpness of imaging may also be greatly enhanced. In
other words, a listener in a vehicle may hear different
sections of the array. Accordingly, when different sections of the loudspeaker array are driven by multi-channel
audio signals, such as left and right stereo signals, distinct and separate imaging of the individual channels may
be achieved. The distinct and separate imaging may be
achieved with minimal cross talk due to the laterally narrowed and focused sound field imaging produced by the
loudspeaker array. In addition, the distinct and separate
imaging may be achieved by the perceived vertically narrowed and focused sound field produced by the combination of the direct and reflected sound.
[0007] Different audio signal processing configurations may also be used to further control the coverage
pattern of the sound field produced by the array of loudspeakers. For example, signal delay may be used to focus audio content produced by the array at the driver
and/or passenger locations. Amplitude shading may also
be used to minimize crosstalk and further focus the array.
Selective application of delay, amplitude shading and inversion to the audio signals driving the loudspeakers in
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the array may form privacy zones for one or more passengers in a vehicle.
[0008] Other systems, methods, features and advantages of the invention will be, or will become, apparent
to one with skill in the art upon examination of the following figures and detailed description. It is intended that all
such additional systems, methods, features and advantages be included within the description, be within the
scope of the invention, and be protected by the following
claims.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The invention can be better understood with reference to the following drawings and description. The
components in the figures are not necessarily to scale,
emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like references numerals designate corresponding parts
throughout the different views.
[0010] FIG. 1 is a plan view of an example vehicle that
includes a sound system.
[0011] FIG. 2 is a block diagram of a portion of an example vehicle and sound system.
[0012] FIG. 3 is a schematic diagram of an example
loudspeaker array as depicted in FIG. 1.
[0013] FIG. 4 is a frequency response graph for an
example loudspeaker array in a vehicle.
[0014] FIG. 5 is a schematic diagram of another example loudspeaker array as depicted in FIG. 1.
[0015] FIG. 6 is a table of a set of delay parameters to
allow aiming of the loudspeaker array depicted in FIG. 5
in a determined direction.
[0016] FIG. 7 is a schematic diagram of still another
example loudspeaker array as depicted in FIG. 1.
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] FIG. 1 is a plan view of a vehicle that includes
an audio system 100. In the illustrated example, the vehicle is a passenger automobile, although other types of
vehicles, such as trucks, buses, boats, motorcycles, and
airplanes are possible in other examples. While a particular example configuration is shown, other configurations
may be used including those with fewer or additional audio system components. The audio system 100 includes
a single line loudspeaker line array 102 and an audio
processing system 104.
[0018] The loudspeaker line array 102 includes a plurality of loudspeakers 106. The loudspeaker line array
102 includes at least four loudspeakers 106 that are
aligned to form a single row. Other configurations of loudspeaker line arrays may also be used, such as multiple
lines of loudspeakers within an array, or configurations
in which the loudspeakers in the line array are positioned
substantially non-linear with respect to each other, such
as offset in the horizontal and/or vertical direction. In ad-
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dition, one or more loudspeaker line arrays may be positioned at various locations within the vehicle.
[0019] The loudspeakers 106 in the loudspeaker line
array 102 may be broadband, such as 20Hz to 20kHz.
In addition, the loudspeakers 106 may be small in diameter, such as about 12.5mm in diameter, 30.0mm in diameter, or any other diameter up to about 50.0mm. Construction of the loudspeakers 106 may include a panel
attached to one or more exciters, and/or no enclosure.
Other loudspeakers 106 may be used, such as those that
include an enclosure. In addition, the exciter(s) may include transducers and/or drivers, such as transducers
coupled with cones or diaphragms. Further, the loudspeakers 106 may be, or may include, an electrodynamic
planar loudspeaker having a radiating surface with a minor axis of 50mm or less and a major axis of any length.
An example loudspeaker is the Odyssey 1 or Odyssey 2
loudspeaker manufactured by Harman Multimedia. Harman Multimedia is a division of Harman International Industries Incorporated of Northridge, CA.
[0020] The audio processing system 104 may be any
combination of hardware and software capable of generating amplified audio signals to drive a loudspeaker.
The audio processing system 104 may include a variety
of audio components such as radios, telephones, game
counsels, CDs, DVDs, their derivatives, such as super
audio, blu-ray and high definition, and the like. The audio
processing system 104 may utilize or produce 1-channel
source material (mono), 2-channel source material such
as left and right stereo audio signals, 5.1 channel audio
signals, 6 channel audio signals, 7.1 channel audio signals, and/or any other source materials. The audio
processing system 104 may control the amplitude,
phase, mixing ratios, equalization, etc. of the audio signals used to drive the loudspeakers 106. Information from
a data bus included in the vehicle, microphones, and/or
any other transduction devices may be used with the audio processing system 104 to control the mixing and aiming parameters.
[0021] Each of the loudspeakers 106 in the loudspeaker line array 102 may be driven by an audio signal provided by a separate channel of an audio amplifier included in the audio processing system 104. Alternatively,
multiple loudspeakers 106 may be driven simultaneously
by an audio signal provided from a single channel of an
audio amplifier. The multiple loudspeakers 106 may be
grouped to be adjacently located loudspeakers 106. Alternatively, the multiple loudspeakers 106 may be scattered symmetrically or un-symmetrically within the loudspeaker line array 102. Each channel of the amplifiers
may also include a processor, such as a digital signal
processor (DSP), that can provide sophisticated
processing including equalization, filtering, delay, and
limiter/compression capability. For example, the frequency response of the loudspeaker line array 102 may be
equalized for a flat response at one or more listener locations within the vehicle.
[0022] The vehicle may also include front speakers,
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side speakers, rear speakers, one or more subwoofers,
seatback speakers, etc. that are driven by the audio
processing system 104 to cooperatively operate with the
loudspeaker line array 102. These other speakers may
include one or more speaker drivers of a predetermined
range of frequency response such as a tweeter, a midrange or a woofer.
[0023] The audio processing system 104 may also include processing, such as digital signal processing (DSP)
technology, to control the acoustic radiation characteristics of the loudspeaker line array 102. Specifically, signal
delay and/or amplitude/phase modifications may be used
to change the coverage pattern of the loudspeaker line
array 102. The processing may also allow interactive aiming of the loudspeaker line array 102 to cover one or more
specific audience areas within a vehicle. Signal delay
and/or amplitude shading may be applied to the loudspeakers 106 in the loudspeaker line array 102 to effectively change the shape of acoustic radiation from the
array by modifying the interaction of the sound waves
between individual transducers.
[0024] In addition, more complicated algorithms may
be applied that superimpose multiple coverage pattern
characteristics on the loudspeaker line array 102 at the
same time. The multiple coverage pattern characteristics
may allow sound fields to be tailored to multiple listening
locations (seats) in the vehicle simultaneously. Additionally, null zones may be created by management of the
phase relation between the loudspeakers 106 in the loudspeaker line array 102. Thus, zoned audio may be created.
[0025] The zoned audio may be limited by bandwidth
limitations that limit the coverage pattern control range
by the ratio of array dimensions vs. wavelength. An illustrative example of such zoned audio would be the capability of listening to two talk radio shows in two different
seats in a vehicle at the same time, without acoustic overlap. This would provide individual audio privacy, as if the
listeners were wearing headphones. The capability to
create zoned audio and null zones, may also greatly contribute to hands-free telephone communication. For example, zoned audio may provide passenger privacy from
the conversation of the driver with a third party in a handsfree telephone conversation. The privacy may be enabled by the driver upon receiving an incoming telephone
call by enabling a "privacy mode" using zoned audio and
null zones.
[0026] The illustrated vehicle includes a number of
substantially flat surfaces that converge at a peripheral
edge with a sound reflective surface that is glass. For
example, a vehicle typically has horizontal shelves that
include an instrument panel dashboard 110, a rear dashboard 112, side window dashboards 114 and a headliner
dashboard 116. The loudspeaker line array 102 may be
positioned in/on one or more of the horizontal shelves
proximate to the adjacently located reflective surface. Accordingly, the line formed by the longitudinally extending
loudspeaker line array 102 may be substantially parallel
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with nearby sound reflective surfaces.
[0027] In the illustrated example, the loudspeaker line
array 102 is positioned in a narrow, shallow area on the
instrument panel dashboard 110 between one or more
defrost vents 118 and a windshield 120. This area desirably does not conflict with mechanical or industrial design
territory utilized by the manufacturer of the vehicle. In
one example, the loudspeaker line array 102 includes
five loudspeakers 106 that are equidistantly spaced
across the entire instrument panel dashboard 110 so that
a first loudspeaker 106 is positioned near one side of the
vehicle, a second loudspeaker 106 is positioned near the
opposite side of the vehicle, and a third, fourth, and fifth
loudspeaker 106 are positioned equidistantly between
the first and second loudspeakers 106 to form a single
horizontal line. In another example, a large number of
loudspeakers 106 may be positioned contiguously to
form a single line stretching horizontally from one side of
the vehicle to the opposite side of the vehicle as illustrated
in FIG. 1. In still other examples, any number of loudspeakers 106 may be spaced equidistantly across the
vehicle to form a single horizontal line. In other examples,
at least a portion of the loudspeakers 106 may not be
positioned equidistantly from each other.
[0028] Since the instrument panel dashboard 110
must fit within the cabin of the vehicle, the instrument
panel dashboard 110 extends substantially across the
width of the vehicle. For example, the instrument panel
dashboard may be 5-10mm shorter than the inside diameter of the vehicle cabin. In addition, since the loudspeaker line array 102 may not extend completely to the
opposite edges of the instrument panel dashboard, the
loudspeaker line array 102 may substantially extend almost the full width of the vehicle. For example, a proximate and a distal end of the loudspeaker line array 102
may be positioned 10-30mm away from the boundary
provided by the interior wall of the vehicle cabin.
[0029] The loudspeaker line array 106 may form a line
that is substantially parallel to the windshield 120. In one
example, the line formed by the loudspeaker line array
106 may be a straight line. In another example, the loudspeaker line array 106 may form a line with a predetermined radius of curvature. In still another example, the
loudspeaker line array 106 may form a line that includes
a plurality of different, or the same, radii of curvature. In
yet another example, the loudspeaker line array 106 may
form a line with at least one straight section and at least
one section with a radius of curvature.
[0030] The positioning of the loudspeaker line array
102 in close proximity to the convergence of the instrument panel dashboard 110 and the windshield 120 may
reduce the need for other loudspeaker locations, and
avoid conflicts related to available per-vehicle equipment
locations. In addition, due to the close proximity of an
angled, sound reflective surface provided by the windshield 120, the loudspeaker line array 102 may be optimized for sound imaging, and to provide a well-defined
image.
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[0031] In another example, or in addition, the loudspeaker line array 102 may be positioned in the rear deck
dashboard 112 in close proximity to a rear windshield
122 of the vehicle. In still another example; or in addition,
the loudspeaker line array 102 may be positioned in one
or more of the side window dashboards 114 in close proximity to a corresponding side windshield 124. With a loudspeaker line array 102 positioned in multiple side window
dashboards 114 on the same side of the vehicle, each
side window dashboard 114 may have an individual loudspeaker line array 102, or a single loudspeaker line array
102 may be split among the multiple side window dashboards 114. In yet another example, or in addition, the
loudspeaker line array 102 may be positioned in the
headliner dashboard 116 in close proximity to one or
more corresponding side windshields 124.
[0032] FIG. 2 is a block diagram cutaway view of a
portion of the vehicle illustrated in FIG. 1 that includes
the instrument panel dashboard 110, the windshield 120
and one of the loudspeakers 106 of the loudspeaker line
array 102. For purposes of clarity, only one loudspeaker
106 of the loudspeaker line array 102 is illustrated, however all the loudspeakers 106 in the loudspeaker array
may be similarly illustrated and described. The loudspeaker 106 is strategically positioned between the defroster vent 118 and a point of intersection 202 of the
instrument panel dashboard 110 and the windshield 120.
In the illustrated example, the loudspeaker 106 is spaced
away from the intersection point 202 by a predetermined
distance "X." As described later, the loudspeaker 106
may be positioned in close proximity to the point of intersection 202 to achieve desirable vertically widened pattern coverage while providing vertical narrowing of the
sound field perceived by a listener. Accordingly, the predetermined distance "X" may be as small as possible and
can be only that amount of distance required to accommodate the physical dimensions of the loudspeaker 106.
[0033] Typically, the surface of the instrument panel
dashboard 110 and the surface of the windshield 120 do
not actually intersect but rather converge at the point of
intersection 202. This point of convergence is typically
along a peripheral edge of the instrument panel dashboard 110 and a portion of the surface of the windshield
120. Accordingly, an angle (θ) between the instrument
panel dashboard 110 and the windshield 120 extending
above the instrument panel dashboard 110 is formed
based on the rake, or slope of the windshield 120 with
respect to the instrument panel dashboard 110.
[0034] The loudspeaker 106 may be mounted in the
instrument panel dashboard 110 with a front surface of
the loudspeaker 106 substantially parallel to the surface
of the instrument panel dashboard 110 and facing substantially vertically. Since the instrument panel dashboard 110 may be formed with various elevations and
features, the loudspeaker line array 102 is substantially
parallel with the instrument panel dashboard 110. The
front surface of each of the loudspeakers 106 may also
be at least partially facing the windshield 120. When each
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of the loudspeakers 106 in the loudspeaker line array
102 is driven with an audio signal, sound waves will emanate from the front surface of each of the loudspeakers
106.
[0035] Due to the omni-directional nature of the loudspeakers 106, sound waves emanated from the loudspeakers 106 may be identified as direct sound impulses
204 and reflected sound impulses 206. In addition, due
to the relatively small diameter of the loudspeakers 106,
such as 19mm, the impulses 204 and 206 are relatively
large amplitude and relatively short duration when compared to larger diameter loudspeakers, such as 90mm
diameter loudspeaker. A portion of the direct sound impulses 204a may be sound waves that are not reflected
or otherwise impeded by sound reflective and/or sound
absorbing surfaces. The reflected sound impulses 206
may be created by the reflection of some of the direct
sound impulses 204b by the windshield 120. As a result
of the reflection, a virtual loudspeaker 210 is created on
the opposite side of the windshield 120 from where the
loudspeaker 106 is located.
[0036] The virtual loudspeaker 210 is rotated to a substantially vertical position. The position of the virtual loudspeaker 210 may be substantially vertical due to the angle of the windshield 120. The angle of the windshield
120 may vary between about 30 degrees and about 90
degrees. At a windshield angle of 45 degrees, for example, the front surface of the virtual loudspeaker 210 is
perpendicular to the front surface of the loudspeaker 106.
If the angle of the windshield is less than 45 degrees, the
front surface of the virtual loudspeaker 210 may be angled toward the instrument panel dashboard 110. If on
the other hand, the angle of the windshield 120 is greater
than 45 degrees, the front face of the virtual loudspeaker
210 may be angled away from the instrument panel dashboard 110.
[0037] The virtual loudspeaker 210 may provide the
reflected sound impulses 206 at a vertical distance "Y"
above the instrument panel dashboard 110. The vertical
distance is based on the distance between the front surface of the loudspeaker 106 and the surface of the windshield 120. In addition, the vertical distance is due to the
angle (θ) of the windshield 120, such as 30 degrees, 35
degrees, 40 degrees, 45 degrees and 50 degrees. Due
to the reflection, the path of the reflected sound impulses
206 is slightly longer than the path of the direct sound
impulses 204. In other words, there can be some phase
difference between the direct sound impulses 204 and
the reflected sound impulses 206.
[0038] To minimize the phase difference, the loudspeaker 106 may be positioned substantially at the intersection 202. Due to physical loudspeaker mounting constraints, the loudspeaker 106 may be mounted proximate, adjoining or juxtaposed to the intersection 202, at
a location that is substantially at the intersection 202.
Minimization of the phase difference may be achieved
by minimizing the difference in path length between the
direct sound impulses 204a and the reflected sound im-
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pulses 206.
[0039] Minimization of the phase difference allows the
direct sound impulses 204a and the reflected sound impulses 206 from the same loudspeaker 106 to be constructively combined substantially in phase to form a perceived single sound source. "Substantially in phase" is
defined as a phase shift between frequencies that is less
than 90 degrees between about 100Hz and about 10kHz.
The perceived single sound source also creates the perception by a listener of a resulting vertical sound field that
is narrowed and focused due to the relatively close proximity of the loudspeaker 106 and the virtual loudspeaker
210. Due to the combination of the direct and reflected
sound impulses 204 and 206, however, the vertical coverage is actually widened. Accordingly, variations in listener height with respect to the loudspeaker line array
still provides the perceived effect of a narrowed, focused
and well-defined vertical sound field.
[0040] Each of the loudspeakers 106 in the loudspeaker line array 102 may constructively combine the direct
sound impulses 204a of the loudspeaker 106 with reflected sound impulses 206 of the same loudspeaker 106.
Thus, the magnitude of the direct and reflected sound is
substantially similar. "Constructive combination" of impulses is defined as the combination of two sound waves
to form a sound wave with a frequency response deviation that averages less than +/- 5 dB between about
100Hz and about 10kHz.
[0041] As a result of the combination of "two" audio
sources (the actual and virtual loudspeakers), the sensitivity and the sound output may be doubled in magnitude.
Due to the close proximity of the angled sound reflective
surface of the windshield 120, the vertical sound coverage is widened, while a perceived sound field is a vertically narrowed, sharp, well-defined image. In addition,
due to the single line loudspeaker array configuration,
the perceived sound image is also horizontally sharp.
Accordingly, the resulting coverage pattern produced by
the loudspeaker line array 102 is a sound field perceived
by a listener to be narrowed and focused both vertically
and laterally. Due to the vertically and laterally focused
sound field, imaging and perception of sound images produced by the loudspeaker line array 102 may be extremely sharp, clear, well defined, and of a finite size.
[0042] in a vehicle, the loudspeaker line array 102 may
be oriented with its major axis horizontal. In this orientation, the loudspeaker line array 102 may be enabled to
provide coverage pattern control along the horizontal axis. In addition, the location of the loudspeaker line array
102 in close proximity, adjoining or juxtaposed to the intersection 202 of the instrument panel (IP) dashboard
110 and the windshield 120 forms acoustic reflections or
virtual (mirror) images of each of the loudspeakers 106
in the loudspeaker line array 102. As a result, the effective
sensitivity and maximum output of the loudspeaker line
array 102 is increased. In addition, the loudspeaker line
array 102 may also include coverage pattern control in
the horizontal axis and perceived coverage pattern con-
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trol in the vertical axis. For optimal coverage the distance
between adjacent loudspeakers 106 can be calculated
vs. the acoustic wavelength of the reproduced frequencies. The side-to-side and up-down variation in frequency
response of the loudspeaker line array 102 may also be
monitored and effectively controlled.
[0043] FIG. 3 is a schematic illustrating an example
curved loudspeaker line array 302 mounted in a vehicle.
In this example, the loudspeaker line array 302 includes
fifty four contiguously aligned loudspeakers that are positioned on an instrument panel dashboard to form a single line loudspeaker array in close proximity to a windshield of a vehicle as previously described. In other examples any other number of loudspeakers may form the
loudspeaker line array 302 in other previously described
locations in a vehicle. The loudspeaker line array 302
may have a determined width (W) 304 that is substantially
the width of the vehicle. Other widths may be used, such
as a portion of the width of the vehicle. The loudspeaker
line array 302 may be positioned to form a determined
radius of curvature (R) 306 that corresponds to the radius
of curvature of the windshield of the vehicle. In the illustrated example, the width (W) 304 may be about 1146
cm and the radius of curvature (R) 306 may about
1870cm based on the width (W) 304. In other examples,
the radius of curvature (R) 306 may be less than 2 meters
and the width (W) 304 may be less than 1.5 meters. Each
of the loudspeakers in the example loudspeaker line array 302 is a 19mm diameter wide-band driver (about
350Hz to about 20kHz).
[0044] The loudspeaker line array 302 may be mounted in the instrument panel dashboard. Alternatively, the
loudspeaker line array 302 may use fifty-four individual
modular loudspeaker/enclosure combinations. The loudspeakers in the array may be contiguously positioned
with predetermined center-to-center lateral spacing. The
center-to-center lateral spacing of the loudspeakers in
the example loudspeaker line array 302 is about 21.6
mm. The audio signals driving the loudspeaker line array
302 may also drive other loudspeakers positioned away
from the loudspeaker line array 302, such as 200mm
woofers positioned in the front doors of the vehicle. The
audio signals provided to the other loudspeakers may be
filtered. Loudspeakers that are woofers for example, may
receive audio signals that are high pass filtered at about
400 Hz.
[0045] In FIG. 3, a front driver position 310 and a front
passenger position 312 are also illustrated. The positions
310 and 312 are positioned a determined range of distance (D) 314 depending on the slidable location of the
front seats of the vehicle. The distance (D) is positioned
within the near field of the loudspeaker line array 302.
The nearfield of a loudspeaker is determined based on
the size of the sound source. In the case of single line
loudspeaker array, the size of the sound source may be
the length of the loudspeaker array. Each of the positions
310 and 312 are also away from a central axis 316 of the
loudspeaker line array 302 by a determined distance (C)
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318. In the illustrated example, the determined distance
(C) 318 is about 37 cm.
[0046] Objective and subjective performance testing
was performed using the loudspeaker line array 302 in
a various configurations. In a first example configuration,
a single audio signal (mono) was used to drive the entire
loudspeaker line array 302. In this example, good coverage of all points across the front seating area of the
vehicle was experienced. The perceived sound source
width was relatively narrow and was perceived to come
from a single loudspeaker in the loudspeaker line array
302. As the listener moved horizontally from side to side
in front of the loudspeaker line array 302, the sound
source appeared to always originate from a point directly
in front of the listener due to the narrowed and focused
lateral coverage pattern of the sound field being produced. Accordingly, when the listener is positioned along
the central axis 316 of the loudspeaker line array 302,
centered mono sources were particularly effective audio
source material because they may sound like they are
coming from the exact center of the loudspeaker line array 302, as if only a center loudspeaker (loudspeaker 27
in the illustrated example) of the loudspeaker line array
302 were operating, while a listener is actually receiving
the horizontal and vertical coverage pattern of the entire
loudspeaker line array 302.
[0047] FIG. 4 is a set of frequency response curves
based on driving the entire loudspeaker line array 302 of
FIG. 3 with a single (mono) audio signal that is not equalized. In FIG. 4, a first unequalized frequency response
402 of the loudspeaker line array 302 at the front driver
position 310 is illustrated. In addition, an unequalized frequency response 404 at the front passenger position 312
is also illustrated. Finally, an unequalized frequency response 406 at a center position 320 located on the central
axis 316 at distance (D) 314 (FIG. 3) is illustrated.
[0048] As is readily apparent, use of the loudspeaker
line array 302 has dramatically reduced the amount of
deviation in frequency response that would otherwise be
present in many conventional audio systems in vehicles.
Each of the frequency responses of the loudspeaker line
array 302 at the front driver position 310, the center position 320, and the front passenger position 312 are substantially similar due to the narrowed and focused vertical
and lateral coverage pattern of the sound field provided
by the loudspeaker line array 302. Raw frequency responses of the loudspeaker array at the front driver position 310, the center position 320, and the front passenger position 312 may include a 3-dB/octave high-frequency roll off as illustrated. The roll off may be due to the
curvature of the loudspeaker line array 302. The response of a single loudspeaker in the loudspeaker line
array 302 may be essentially flat.
[0049] In FIG. 3, in another example configuration, the
loudspeaker line array 302 may be driven in stereo with
the right half of the array (drivers 1-27) fed by the right
audio channel and the left half of the array (drivers 28-54)
fed by the left audio channel. In this example configura-
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tion, no delay or shading of the individual loudspeakers
in the array was in effect, however equalization may be
used to correct for the 3-dB/ocatave high-frequency roll
off. With stereo program material, a distinctly different
sound field effect was experience with loudspeaker line
array 302 than with a mono signal. When listening from
the center or near center position 320, a sharp, well-defined stereo image was created with pinpoint stereo images of panned signals all across the width of the loudspeaker line array 302.
[0050] Center stereo images may also be particular
impressive because the image may similarly be perceived by the listener to originate from a single loudspeaker 106 at substantially the center of the instrument
panel dashboard due to the horizontal narrowed and focused coverage pattern of the loudspeakers in the loudspeaker line array 302. In addition, due to the perceived
vertically narrowed and focused coverage pattern created with the reflected acoustic sound, imaging may be
perceived by the listener to originate from the combination of the loudspeaker line array and the reflected acoustic sound irrespective of the elevation of the listener with
respect to the loudspeaker line array 302.
[0051] The perception of well-defined, pinpoint stereo
images was based on the directional characteristics of
the loudspeaker line array 302 created by the narrow and
focused sound field. In addition, the narrowed and focused sound field may allow a listener to hear sound
emanating from different portions of the loudspeaker line
array 302. In other words, due to the vertically and horizontally tight and focused beam like nature of the perceived sound field produced by the individual loudspeakers 106, different loudspeakers 106, or sections of loudspeakers 106 in the array may be heard by each ear of
a listener. Accordingly, the directionality of the narrowed
and focused sound field may effectively provide cross
talk cancellation by maintaining separation of respective
beams of the left and right stereo signals. In other words,
the left half of the loudspeaker line array 302 may provide
a sound field for the left ear of a listener and the right half
of the loudspeaker line array 302 may provide a sound
field for the right ear of the listener.
[0052] FIG. 5 is a schematic diagram of the loudspeaker line array 302 in another example configuration. Similar to the previous example configuration, the loudspeaker line array 302 may be driven in stereo with the right
half of the array (drivers 1-27) fed by the right audio channel and the left half of the array (drivers 28-54) fed by the
left audio channel. In this example, however, in order to
improve the stereo imaging at the front driver location
310, the loudspeaker line array 302 may be both straightened and aimed at the front driver position 310. Straightening and aiming the loudspeaker line array 302 may be
performed by the use of delays. Selective delay of each
of the audio signals driving each of the loudspeakers in
the loudspeaker line array 302 may be used to steer
and/or aim the soundfield/imaging produced by the array.
[0053] Signal processing delay of the audio signals
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EP 1 634 479 B1
used to drive the loudspeaker line array 302 may be used
to both straighten and aim the loudspeaker line array 302
at the positions 310 and 312. Alternatively, the loudspeaker line array 302 may be straightened to be aimed
at the central position 320 or any other location in the
vehicle. The loudspeaker line array 302 was straightened
and aimed at a determine angle (A) 502 toward the front
driver position 310 to provide a virtual straight-line array
aimed at the front driver position 310. In one example,
the determined angle (A) 502 may be about 18.8 degrees.
[0054] FIG. 6 is a table providing example shift values
and corresponding delays for each loudspeaker (N) 602
in the loudspeaker line array 302 illustrated in FIG. 5.
The shift values 604 represent the distance that each
loudspeaker 602 in the loudspeaker line array 302 should
be shifted, or physically moved, to reform the array as a
straight line aimed at the front driver position 310. The
delay 606 in milliseconds provides an example delay of
each loudspeaker 602 that simulates the amount of shift
or movement of each loudspeaker 602. The sample
number 608 is representative of the clock speed at which
an example signal processing system operates. Accordingly, the delay may be rounded to coincide with the clock
speed of the signal processing system. In FIG. 6, the
clock speed of the example signal processing system is
48kHz.
[0055] In this example configuration, the positive imaging characteristics of the previous configurations were
experienced, but now at the front driver location 310. Pinpoint imaging was preserved all along the horizontal line
of the loudspeaker line array 302. Center images were
particular impressive due the combination of the direct
sound impulses and the reflected sound impulses and
the crosstalk cancellation to form a narrowed and focused sound beam. It was perceived that the center images seemed to originate from the center of the loudspeaker line array 302 at the elevation of the direct impulses and the reflected impulses, as if only a source at
that location were operating.
[0056] FIG. 7 is a schematic diagram of the loudspeaker line array 302 in yet another example configuration.
This example configuration is configured to provide
sound field coverage of audio content for both the front
driver location 310 and the front passenger location 312.
To provide such dual sound field coverage, alternate
loudspeaker drivers in the loudspeaker line array 302
may be respectively aimed at the front driver position 310
and/or at one or more of the passengers in the vehicle
using delays. In this example, the loudspeaker line array
302 was simultaneously aimed at both the front driver
position 310 and the front passenger position 312 to obtain sound field coverage on both sides of the vehicle at
the same time and provide audio content.
[0057] Portions of the loudspeaker line array 302 were
straightened and aimed at a determined angle (A) 502
toward the front driver position 310 to provide a first virtual
straight-line array aimed at the front driver position 310.
In addition, portions of the loudspeaker line array 302
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were straightened and aimed at a determined angle (B)
702 toward the front passenger position 312 to provide
a second virtual straight-line array aimed at the front passenger position 312. Accordingly, a first portion of the
sound field produced by the loudspeaker line array 302
may be aimed in a first direction and a second portion of
the sound field produced by the loudspeaker line array
302 may be aimed in a second direction. In the illustrated
example, the determined angles were each about 18.8
degrees.
[0058] In the example configuration, all even numbered loudspeaker drivers in the loudspeaker line array
302 were aimed at the front driver position 310 and all
odd numbered loudspeaker drivers were aimed at the
front passenger position 312. In other examples, other
configurations of the array may be used, such as, predetermined groups of loudspeakers in the array, repetitive patterns of loudspeakers in the array, etc, to aim the
array at the front driver position and/or one or more passenger positions in a vehicle.
[0059] In still other examples, the loudspeaker line array 302 may be dynamically adjusted to maximize coverage based on variable vehicle related parameters such
as vehicle occupancy, seat positions, window positions,
etc. Dynamic adjustments of the loudspeaker line array
302 may be performed automatically by the audio
processing system 104 (FIG. 1). The dynamically adjusted configurations may be adjusted automatically based
on external sensors, user configurable settings, or any
other variable parameters that may be used to identify a
particular configuration of the loudspeaker line array 302.
For example, the user configurable setting may be a
switch or button to manually change the pattern coverage. In addition, the loudspeaker line array 302 may be
dynamically aimed based on the audio content or program material driving the loudspeakers in the loudspeaker line array 302. For example, the imaging produced by
the loudspeaker line array 302 for music may be different
than the imaging for speech, such as a telephone conversation. Detection of the audio content or program material may be automatic, based on the origin, such as a
CD player or a cellular phone, of the audio content or
program material, or manual based on a user configurable setting(s).
[0060] The loudspeaker line array 302 may also be
configured to provide sound field management for each
of one or more occupants in the vehicle. For example,
the loudspeaker line array 302 may be configured to produce a privacy zone for a particular seat location in a
vehicle. The privacy zone may be created using a portion
of the loudspeaker line array 302 to aim desired audio
content at a desired location, and using another portion
of the loudspeaker line array 302 to aim inverted audio
content to cancel sound "leaking" from around the desired location. This may be referred to as a null zone.
The inverted audio content may also be further delayed,
in addition to aiming, to effectively cancel the "leaking"
sound.
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EP 1 634 479 B1
[0061] For example, when a first vehicle occupant is
listening to a talk show while a second vehicle occupant
receives navigation directions, the audio content of the
navigation directions in the sound field of the first occupant may be cancelled by the inverted sound field of the
navigation directions. Similarly, the audio content of the
talk show may be inverted and aimed into the second
occupant’s sound field to cancel "leakage" from the
sound field of the first occupant. Accordingly, by aiming
audio content with selected drivers in the loudspeaker
line array 302, sound cancellation may be maximized.
Such precise aiming and coverage pattern-ability is made
possible by the vertically and laterally narrowed and focused perceived beam of sound produced by the loudspeaker line array 302. Not only is substantially precise
cancellation possible, but minimization of cross talk due
to the cross talk cancellation also maximizes the privacy
of the privacy zone(s).
[0062] In another example configuration the loudspeaker line array 302 was driven by a stereo signal as
previously discussed, without shading but was aimed simultaneously at both the front driver position 310 and the
front passenger position 312 using multiple delays applied to each of the loudspeakers in the loudspeaker line
array 302. This example configuration allows all the loudspeakers to cover multiple positions in the vehicle at the
same time. In addition, this example configuration effectively creates two virtual straight-line arrays crossed at
the centerline 316. Multiple delays may be used to create
imaging within a vehicle occupant’s sound field representative of multiple sources of audio content, such as
representations of a right rear or left rear loudspeaker
positioned behind the occupant. The use of multiple delays may also be used to simulate surround sound, logic
7 or other multi-channel output sound field effects. In addition, the loudspeaker line array 302 may be configured
to cooperatively operate with other loudspeakers within
the vehicle, such as the previously discussed woofers,
to further enhance an occupant’s sound field and/or the
imaging therein.
[0063] In still another example configuration the loudspeaker line array 302 was driven by a stereo signal and
aimed at the front driver position 310 as previously discussed with reference to FIG. 5. In this example, the audio signals provide to selected loudspeaker drivers within
the loudspeaker line array 302 were attenuated to further
aim the sound field imaging produced by the loudspeaker
line array 302. This form of attenuation may be referred
to as Legendre shading, and may be determined with the
Legendre shading function. In the example configuration,
the audio signals to the center loudspeaker drivers in the
loudspeaker array (such as drivers 20-30) were at full
amplitude, and the audio signal levels were gradually and
uniformly decreased so that the drivers at the outside
edges of the loudspeaker line array 302 were attenuated
by a determined amount, such as about +12 dB.
[0064] In an alternative example configuration, the level of the audio signals provided to the outside loudspeak-
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er drivers may be at full amplitude and the amplitude of
audio signals may be smoothly attenuated to decrease
a determined amount, such as about -12 dB at the loudspeaker drivers near the central axis 316 of the loudspeaker line array 302. In yet another example, the loudspeaker line array 302 may be divided into a first section
and a second section. The level of the audio signals provided to the loudspeaker drivers at the center of each
respective section may be at full amplitude, and the amplitude of audio signals may be smoothly attenuated to
decrease a determined amount, such as about -12 dB at
the loudspeaker drivers near the periphery of the respective sections. In other examples, other configurations of
Legrandre shading functions may be used to create constructive and destructive sound waves and provide beam
aiming within a sound field produced by the loudspeaker
line array 302.
[0065] In still one more example configuration, the
loudspeaker line array 302 was driven by a stereo signal
without shading or delays. In this example configuration,
the loudspeaker array was divided into three equal sections: left: loudspeaker drivers 1-18, center: loudspeaker
drivers 19-36, and right: loudspeaker drivers 37-54. The
left stereo signal (L) was routed to the left group of loudspeakers, the right stereo signal (R) was routed to the
right group of loudspeakers, and a mono left plus right
stereo signal (L+R) was routed to the center group of
loudspeakers. Once again the focused and narrow vertical and lateral coverage pattern of the loudspeaker line
array 302 provided the perception of sharp imaging in
each of the three sections. In other examples, the loudspeaker line array 302 may be divided into any number
of sections to simulate various imaging and/or null zones
as previously discussed.
[0066] The previously discussed sound system includes a loudspeaker line array configured to be installed
in a vehicle. The loudspeaker line array is configured to
be positioned on a horizontal shelf in the vehicle in close
proximity to a sound reflective surface. When each of the
loudspeakers included in the array are driven by one or
more audio signals, a sound field or sound beam is produced. The sound field is formed from the combination
of direct sound and reflected sound. The direct sound
and reflected sound from each of the loudspeakers are
combined to form widened vertical coverage and narrow,
focused highly laterally directed coverage. As a result, a
laterally sharp well-defined image, and a vertically sharp
well defined image are perceived by a listener positioned
in the near field produced by the loudspeaker line array.
Due to the combination of the direct sound and the reflected sound, the sensitivity and the amplitude of the
sound waves is increased. In addition, pinpoint imaging
of the sound source is manifested along the length of the
loudspeaker line array.
[0067] While various embodiments of the invention
have been described, it will be apparent to those of ordinary skill in the art that more embodiments and implementations are possible that are within the scope of the
17
EP 1 634 479 B1
invention.
froster vent (118) also positioned in the dashboard
(110).
Claims
7.
The audio system (100) of claim 5, where the at least
four loudspeakers (106) each have a diameter of less
than 50 millimeters.
8.
The audio system (100) of claim 5, where the line is
a single line having a predetermined radius of curvature.
9.
The audio system (100) of claim 5, where the line is
a single line having a plurality of predetermined radii
of curvature.
5
1.
An audio system (100) for use in a vehicle, the audio
system (100) comprising:
a line array (102) of at least four loudspeakers
(106); and
a substantially horizontal shelf configured to be
installed in a vehicle,
where the array is mounted on the shelf and
adapted to be positioned adjacent to a sound
reflective surface that extends above the shelf
and forms a determined angle between the shelf
and the sound reflective surface,
when mounted, the line array (102) is positionable juxtaposed to a convergence of the sound
reflective surface and the shelf with a front face
of each of the loudspeakers (106) positioned to
be substantially parallel to the surface of the
shelf; and
where the loudspeakers (106) are positionable
in the shelf with respect to the sound reflective
surface so that a direct sound impulse provided
by each of the loudspeakers (106) is constructively combined with a reflected sound impulse
created from the same respective loudspeaker
as a result of a minimization of the difference in
path length between the direct sound impulse
and the reflected sound impulse.
2.
3.
The audio system (100) of claim 1, where the loudspeakers (106) are omni-directional, and are configured to enable coverage pattern control in a horizontal axis of a sound field generated by the loudspeakers (106).
The audio system (100) of claim 1, where the shelf
has a length that extends to substantially a width of
the vehicle, and the loudspeakers (106) are positioned in the shelf substantially equidistant from each
other along the length.
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10. The audio system (100) of claim 5, where the line
forms a single straight line.
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4.
The audio system (100) of claim 1, where the loudspeakers (106) are positioned contiguously to each
other to form a single line that substantially extends
a length of the shelf.
5.
The audio system (100) of claim 4, where the sound
reflective surface is a windshield (120) of a vehicle
and the substantially horizontal shelf is a dashboard
(110) of the vehicle.
6.
The audio system (100) of claim 5, where the at least
four loudspeakers (106) are positioned in the dashboard (110) between the windshield (120) and a de-
18
11. The audio system (100) of claim 5, where the at least
four loudspeakers (106) are positioned in the dashboard (110) to face substantially vertically, and a
sound field is formable with a constructive combination of direct sound impulses from the loudspeakers
(106) and direct sound impulses from the loudspeakers (106) that are reflected with the windshield (120).
12. The audio system (100) of claim 5, where the loudspeakers (106) are cooperatively operable to generate a controllable horizontal sound field using a
direct sound impulse generated by the loudspeakers
(106), and each of the loudspeakers (106) are also
operable to generate a vertical sound field from the
constructive combination of a first portion of the direct sound impulse and a reflected sound impulse
provided by reflection from the windshield (120) of a
second portion of the direct sound impulse.
13. The audio system (100) of claim 5, where the at least
four loudspeakers (106) may be configured to aim
audio content at a first predetermined location and
also aim audio content at a second predetermined
location that is different from the first predetermined
location.
14. The audio system (100) of claim 1, comprising an
audio processing system (104) configured to direct
a first audio signal to a first half of the line array (102)
and a second audio signal to a second half of the
line array (102).
50
15. The audio system (100) of claim 14, where the first
audio signal is a left stereo signal and the second
audio signal is a right stereo signal.
55
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16. The audio system (100) of claim 14, where the loudspeaker line array (102) is a single line array (102)
configured to produce a sound image for a listener
that is perceived to emanate from only one of the
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EP 1 634 479 B1
loudspeakers (106) that is closest to the listener.
17. The audio system (100) of claim 14, where the loudspeakers (106) in the loudspeaker line array (102)
are driven by audio signals that are delayed individually to aim a first portion of the sound field produced
by the line array (102) in a first direction and aim a
second portion of the sound field produced by the
loudspeaker line array (102) in a second direction.
5
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18. The audio system (100) of claim 17, where the loudspeakers (106) in the loudspeaker line array (102)
that are positioned adjacently are driven to aim different portions of the sound field.
15
19. The audio system (100) of claim 17, where the loudspeakers (106) in the loudspeaker line array (102)
are divided into a first group and a second group to
aim the respective first portion and the second portion of the sound field.
20. The audio system (100) of claim 14, where the loudspeaker line array (102) may be configured with a
first portion of the loudspeaker line array (102) to aim
audio content at a first predetermined location and
a second portion of the loudspeaker line array (102)
to aim audio content at a second predetermined location.
21. The audio system (100) of claim 1, where a plurality
of loudspeakers (106) in the single line array (102)
are selectively provided delayed audio signals based
on at least one changeable parameter associated
with the vehicle.
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22. The audio system (100) of claim 21, where the at
least one changeable parameter is a user configurable setting.
23. The audio system (100) of claim 21, where the at
least one changeable parameter is an indication of
audio content related to a phone conversation.
24. The audio system (100) of claim 1, where a plurality
of loudspeakers (106) in the single line array (102)
are selectively provided a first group of delayed audio
signals when the audio content is music and a second group of delayed audio signals when the audio
content is voice.
are provided a delayed audio signal to aim audio
content at a first predetermined location and a second group of loudspeakers (106) in the single line
array (102) are provided a delayed audio signal to
aim audio content at a second predetermined location.
27. The audio system (100) of claim 26, where each of
the loudspeakers (106) in the first group is positioned
adjacent to at least one of the loudspeakers (106) in
the second group.
28. The audio system (100) of claim 1, where the single
line array (102) may be configured with a first portion
of the single line array (102) to aim non-inverted audio content at a predetermined location and a second
portion of the single line array (102) to aim the same
audio content that has been inverted at a second
predetermined location to cancel said non-inverted
audio content.
29. The audio system (100) of claim 28, where the noninverted audio content is aimed using delay, and
where the same audio content that has been inverted
has been aimed using delay and the same audio
content that has been inverted is also subject to additional delay.
30. The audio system (100) of claim 1, where the constructive combination results in a sound field frequency response that averages less than plus and
minus 5 decibels between 100 Hertz and 10,000
Hertz.
31. The audio system (100) of claim 1, where the direct
sound impulse and the reflected sound impulse combine substantially in phase due to the proximity of
the loudspeakers (106) to the sound reflective surface.
40
32. The audio system (100) of claim 31, where the loudspeakers (106) are formed in a single line array (102)
in a dashboard (110) of a vehicle and the sound reflective surface is a windshield (120) of the vehicle.
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25. The audio system (100) of claim 1, where a plurality
of loudspeakers (106) in the single line array (102)
are provided delayed audio signals to aim audio content at both a first predetermined location and a second predetermined location.
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26. The audio system (100) of claim 1, where a first group
of loudspeakers (106) in the single line array (102)
33. The audio system (100) of claim 32, where the loudspeakers (106) are formed in a line array (102) that
has a radius of curvature that substantially corresponds to a radius of curvature of the sound reflective
surface.
34. The audio system (100) of claim 31, where the single
line array (102) is positioned in a surface substantially at the point where the line array (102) converges
with the sound reflective surface to form a determined angle.
35. The audio system (100) of claim 31, where the sur-
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face is a longitudinally extending substantially horizontal surface and the sound reflective surface longitudinally extends adjacent to the horizontal surface
such that the line array (102) is positioned substantially in parallel with the surface and at least partially
facing toward the sound reflective surface.
36. The audio system (100) of claim 31, where the direct
sound impulses and the reflected sound impulse are
produced from a single loudspeaker in the line array
(102).
37. The audio system (100) of claim 31, where substantially in phase is when the phase shift between the
direct sound impulse and the reflected sound impulse is less than 90 degrees out of phase between
100 Hz and 10 kHz.
Patentansprüche
1.
in einer horizontalen Achse eines Schallfelds, das
von den Lautsprechern (106) erzeugt wird, zu ermöglichen.
5
3.
Das Audiosystem (100) von Anspruch 1, in dem das
Bord eine Länge aufweist, die sich im wesentlichen
über die Breite des Fahrzeugs erstreckt, und die
Lautsprecher (106) in dem Bord entlang der Länge
im wesentlichen äquidistant zueinander positioniert
sind.
4.
Das Audiosystem (100) von Anspruch 1. in dem die
Lautsprecher (106) zu einander benachbart positioniert sind, so dass sie eine einzelne Linie bilden, die
sich im wesentlichen entlang einer Länge des Bords
erstreckt.
5.
Das Audiosystem (100) von Anspruch 4, in dem die
schallreflektierende Oberfläche eine Windschutzscheibe (120) eines Fahrzeugs ist und das im wesentlichen horizontale Bord ein Armaturenbrett (110)
des Fahrzeugs ist.
6.
Das Audiosystem (100) von Anspruch 5, in dem die
zumindest vier Lautsprecher (106) in dem Armaturenbrett (110) zwischen der Windschutzscheibe
(120) und einer Scheibenheizung, die ebenso in dem
Armaturenbrett (110) positioniert ist, positioniert
sind.
7.
Das Audiosystem (100) von Anspruch 5, in dem jeder der zumindest vier Lautsprecher (106) einen
Durchmesser von weniger als 50 Millimeter hat.
8.
Das Audiosystem (100) von Anspruch 5, in dem die
Linie eine einzelne Linie ist, die einen vorbestimmten
Krümmungsradius hat.
9.
Das Audiosystem (100) von Anspruch 5, in dem die
Linie eine einzelne Linie ist, die eine Mehrzahl an
vorbestimmten Krümmungsradien hat.
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20
Ein Audiosystem (100) zur Verwendung in einem
Fahrzeug, wobei das Audiosystem (100) umfasst:
eine Linienanordnung (102) von zumindest vier
Lautsprechern (106); und
ein in wesentlichen horizontales Bord, das dazu
ausgebildet ist, in einem Fahrzeug montiert zu
werden,
wobei die Anordnung auf dem Bord montiert ist
und dazu ausgebildet ist, benachbart zu einer
schallreflektierenden Oberfläche positioniert zu
werden, die sich oberhalb des Bords erstreckt
und einen bestimmten Winkel zwischen dem
Bord und der schallreflektierenden Oberfläche
bildet,
wobei, wenn sie montiert wurde, die Linienanordnung (102) gegenüberliegend einem Zusammenlaufen der schallreflektierenden Oberfläche und des Bords mit einer vorderen Fläche
jedes der Lautsprecher (106) derart positioniert
werden kann, dass sie im wesentlichen parallel
zu der Oberfläche des Bords ist; und
wobei die Lautsprecher (106) in dem Bord derart
mit Bezug auf die schallreflektierende Oberfläche positioniert werden können, dass ein direkter Schallimpuls, der von jedem der Lautsprecher (106) bereitgestellt wird, konstruktiv mit einem reflektierten Schallimpuls, der von dem jeweiligen selben Lautsprecher erzeugt wird, als
ein Ergebnis einer Minimisierung des Unterschieds in der Weglänge zwischen dem direkten
Schallimpuls und dem reflektierten Schallimpuls
kombiniert wird.
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10. Das Audiosystem (100) von Anspruch 5, in dem die
Linie eine einzelne gerade Linie bildet.
45
50
11. Das Audiosystem (100) von Anspruch 5, in dem die
zumindest vier Lautsprecher (106) derart in dem Armaturenbrett (110) positioniert sind, dass sie im wesentlichen vertikal gegenüberliegen, und wobei ein
Schallfeld mit einer konstruktiven Kombination von
direkten Schallimpulsen von den Lautsprechern
(106) und direkten Schallimpulsen von den Lautsprechern (106), die von der Windschutzscheibe
(120) reflektiert werden, gebildet werden kann.
55
2.
12. Das Audiosystem (100) von Anspruch 5, in dem die
Lautsprecher (106) kooperativ betrieben werden
können, so dass ein steuerbares horizontales
Das Audiosystem (100) von Anspruch 1, in dem die
Lautsprecher (106) ungerichtet sind und dazu ausgebildet sind, eine Überdeckungsmustersteuerung
12
23
EP 1 634 479 B1
Schallfeld unter Verwendung eines direkten Schallimpulses, der von den Lautsprechern (106) erzeugt
wird, erzeugt wird, und jeder der Lautsprecher (106)
ebenso betrieben werden kann, dass er ein vertikales Schallfeld aus der konstruktiven Kombination eines ersten Teils des direkten Schallimpulses und eines reflektierten Schallimpulses, der durch Reflexion eines zweiten Teils des direkten Schallimpulses
an der Windschutzscheibe (120) bereitgestellt wird,
erzeugt wird.
13. Das Audiosystem (100) von Anspruch 5, in dem die
zumindest vier Lautsprecher (106) dazu ausgebildet
sein können, einen Audioinhalt an einem ersten vorbestimmten Ort zu richten und ebenso einen Audioinhalt an einem zweiten vorbestimmten Ort zu richten, der von dem ersten vorbestimmten Ort verschieden ist.
14. Das Audiosystem (100) von Anspruch 1, das ein Audioverarbeitungssystem (104) umfasst, das dazu
ausgebildet ist, ein erstes Audiosignal auf eine erste
Hälfte der Linienanordnung (102) und ein zweites
Audiosignal auf eine zweite Hälfte der Linienanordnung (102) zu richten.
und zweiten Bereich des Schallfeldes ausrichten.
5
10
15
20
25
15. Das Audiosystem (100) von Anspruch 14, in dem
das erste Audiosignal ein linkes Stereosignal ist und
das zweite Audiosignal ein rechtes Stereosignal ist.
30
16. Das Audiosystem (100) von Anspruch 14, in dem die
Lautsprecherlinienanordnung (102) eine Einzellinien-Anordnung (102) ist, die dazu ausgebildet ist, ein
Schallbild für einen Hörer zu erzeugen, das so wahrgenommen wird, als ob es lediglich von einem der
Lautsprecher (106) ausgehen würde, der dem Hörer
am nächsten ist.
17. Das Audiosystem (100) von Anspruch 14, in dem die
Lautsprecher (106) in der Lautsprecherlinienanordnung (102) durch Audiosignale betrieben werden,
die individuell verzögert sind, so dass ein erster Teil
des durch die Linienanordnung (102) erzeugten
Schallfeldes in eine erste Richtung gerichtet wird und
zweiter Teil des durch die Lautsprecherlinienanordnung (102) erzeugten Schallfeldes in eine zweite
Richtung gerichtet wird.
18. Das Audiosystem (100) von Anspruch 17, in dem die
Lautsprecher (106) in der Lautsprecherlinienanordnung (102), die benachbart sind, so betrieben werden, dass sie unterschiedliche Bereiche des Schallfeldes ausrichten.
19. Das Audiosystem (100) von Anspruch 17, in dem die
Lautsprecher (106) in der Lautsprecherlinienanordnung (102) in eine erste Gruppe und ein zweite Gruppe unterteilt sind, so dass sie den jeweiligen ersten
24
20. Das Audiosystem (100) von Anspruch 14, in dem die
Lautsprecherlinienanordnung (102) mit einem ersten Teil der Lautsprecherlinienanordnung (102), so
dass sie einen Audioinhalt an einen ersten vorbestimmten Ort richtet, und mit einem zweiten Teil der
Lautsprecherlinienanordnung (102), so dass sie einen Audioinhalt an einen zweiten vorbestimmten Ort
richtet, ausgebildet sein kann.
21. Das Audiosystem (100) von Anspruch 1, in dem an
eine Mehrzahl an Lautsprechern (106) in der Einzellinienanordnung (102) selektiv verzögerte Audiosignale auf der Grundlage von zumindest einem veränderbaren Parameter, der mit dem Fahrzeug assoziiert ist, geliefert werden.
22. Das Audiosystem (100) von Anspruch 21, in dem
der zumindest eine veränderbare Parameter eine
von einem Nutzer konfigurierbare Einstellung ist.
23. Das Audiosystem (100) von Anspruch 21, in dem
der zumindest eine veränderbare Parameter ein Hinweis auf einen Audioinhalt ist, der auf eine Telefonkonversation bezogen ist.
24. Das Audiosystem (100) von Anspruch 1, in dem an
eine Mehrzahl an Lautsprechern (106) in der Einzellinienanordnung (102) selektiv eine erste Gruppe
von verzögerten Audiosignalen geliefert wird, wenn
der Audioinhalt Musik ist, und eine zweite Gruppe
von verzögerten Audiosignalen geliefert wird, wenn
der Audioinhalt Sprache ist.
35
40
45
50
55
25. Das Audiosystem (100) von Anspruch 1, in dem an
eine Mehrzahl an Lautsprechern (106) in der Einzellinienanordnung (102) verzögerte Audiosignale geliefert werden, so dass sie einen Audioinhalt sowohl
an einen ersten vorbestimmten Ort als auch ein zweiten vorbestimmten Ort richten.
26. Das Audiosystem (100) von Anspruch 1, in dem an
eine erste Gruppe von Lautsprechern (106) in der
Einzellinienanordnung (102) ein verzögertes Audiosignal geliefert wird, so dass sie einen Audioinhalt
an einen ersten vorbestimmten Ort richtet, und an
eine zweite Gruppe von Lautsprechern (106) in der
Einzellinienanordnung (102) ein verzögertes Audiosignal geliefert wird, so dass sie einen Audioinhalt
an einen zweiten vorbestimmten Ort richtet.
27. Das Audiosystem (100) von Anspruch 26, in dem
jeder der Lautsprecher (106) in der ersten Gruppe
benachbart zu zumindest einem der Lautsprecher
(106) in der zweiten Gruppe positioniert ist.
28. Das Audiosystem (100) von Anspruch 1, in dem die
13
25
EP 1 634 479 B1
Einzellinienanordnung (102) mit einem ersten Teil
der Einzellinienanordnung (102) ausgebildet sein
kann, so dass er einen nicht-invertierten Audioinhalt
an einen vorbestimmten Ort richtet, und einen zweiten Teil der Einzellinienanordnung (102), so dass er
denselben Audioinhalt, der invertiert worden ist, an
einen zweiten vorbestimmten Ort richtet, so dass der
genannten nicht-invertierte Audioinhalt ausgelöscht
wird.
29. Das Audiosystem (100) von Anspruch 28, in dem
das nicht-invertierte Audiosignal unter Verwendung
einer Verzögerung ausgerichtet wird, und in dem
derselbe Audioinhalt, der invertiert worden ist, unter
Verwendung einer Verzögerung gerichtet worden
ist,, und derselbe Audioinhalt, der invertiert worden
ist, zudem eine zusätzliche Verzögerung erfährt.
30. Das Audiosystem (100) von Anspruch 1, in dem die
konstruktive Kombination in einer Schallfeldfrequenzantwort resultiert, die im Durchschnitt weniger
als plus/minus 5 Dezibel zwischen 100 Hertz und
10000 Hertz beträgt.
31. Das Audiosystem (100) von Anspruch 1, in dem der
direkte Schallimpuls und der reflektierte Schallimpuls aufgrund der Nähe der Lautsprecher (106) zu
der schallreflektierenden Oberfläche im wesentlichen in Phase miteinander kombinieren.
überliegend positioniert ist.
5
36. Das Audiosystem (100) von Anspruch 31, in dem die
direkten Schallimpulse und die reflektierten Schallimpulse von einem einzelnen Lautsprecher in der
Linienanordnung (102) erzeugt werden.
10
37. Das Audiosystem (100) von Anspruch 31, in dem im
wesentlichen In-Phase ist, wenn die Phasenverschiebung zwischen dem direkten Schallimpuls und
dem reflektierten Schallimpuls zwischen 100 Hz und
10 kHz kleiner als 90 Grad phasenverschoben ist.
15
Revendications
1.
33. Das Audiosystem (100) von Anspruch 32, in dem die
Lautsprecher (106) in einer Linienanordnung (102)
ausgebildet sind, die einen Krümmungsradius hat,
der im wesentlichen einem Krümmungsradius der
schallreflektierenden Oberfläche entspricht.
34. Das Audiosystem (100) von Anspruch 31, in dem die
Einzellinienanordnung (102) im wesentlichen an
dem Punkt in einer Oberfläche positioniert ist, in dem
die Linienanordnung (102) mit der schallreflektierenden Oberfläche, so dass ein vorbestimmter Winkel
gebildet wird, zusammenläuft.
25
35
40
45
2.
Système audio (100) selon la revendication 1, dans
lequel les haut-parleurs (106) sont omnidirectionnels
et sont configurés de manière à permettre une commande du diagramme de couverture dans l’axe horizontal du champ acoustique généré par les hautparleurs (106).
3.
Système audio (100) selon la revendication 1, dans
lequel la tablette a une longueur qui s’étend sensiblement sur la largeur du véhicule et les hautparleurs (106) sont positionnés dans la tablette de
50
35. Das Audiosystem (100) von Anspruch 31, in dem die
Oberfläche eine sich longitudinal erstreckende im
wesentlichen horizontale Oberfläche ist, und die
schallreflektierende Oberfläche sich benachbart zu
der horizontalen Oberfläche longitudinal derart erstreckt, dass die Linienanordnung (102) im wesentliche parallel zu der Oberfläche und zumindest teilweise der schallreflektierenden Oberfläche gegen-
55
14
Système audio (100) destiné à être utilisé dans un
véhicule, le système audio (100) comprenant :
- un agencement linéaire (102) d’au moins quatre haut-parleurs (106) ; et
- une tablette sensiblement horizontale configurée pour être installée dans un véhicule,
- dans lequel l’agencement est monté sur la tablette et est adapté à être positionné de manière
adjacente à une surface réfléchissant les sons
s’étendant au-dessus de la tablette et fait un angle déterminé entre la tablette et la surface réfléchissant les sons,
- lorsqu’il est monté, l’agencement linéaire (102)
peut être positionné juxtaposé au point de convergence de la surface réfléchissant les sons et
de la tablette, la face avant de chacun des hautparleurs (106) étant positionnée de façon à être
sensiblement parallèle à la surface de la tablette, et
- dans lequel les haut-parleurs (106) peuvent
être positionnés dans la tablette en regard de la
surface réfléchissant les sons, de façon qu’une
impulsion sonore directe fournie par chacun des
haut-parleurs (106) soit combinée de manière
constructive avec une impulsion sonore réfléchie créée par le même haut-parleur respectif
en raison de la minimisation de la différence de
longueur de trajet entre l’impulsion sonore directe et l’impulsion sonore réfléchie.
20
30
32. Das Audiosystem (100) von Anspruch 31, in dem die
Lautsprecher (106) in einer Einzellinienanordnung
(102) in einem Armaturenbrett (110) eines Fahrzeugs ausgebildet sind, und die schallreflektierende
Oberfläche eine Windschutzscheibe (120) des Fahrzeugs ist.
26
27
EP 1 634 479 B1
manière sensiblement équidistante entre eux sur sa
longueur.
4.
5.
6.
Système audio (100) selon la revendication 1, dans
lequel les haut-parleurs (106) sont positionnés de
façon contiguë entre eux de manière à former une
ligne unique s’étendant sensiblement sur la longueur
de la tablette.
d’une seconde partie de l’impulsion sonore directe.
5
Système audio (100) selon la revendication 4, dans
lequel la surface réfléchissant les sons est le parebrise (120) d’un véhicule et la tablette sensiblement
horizontale est le tableau de bord (110) du véhicule.
10
Système audio (100) selon la revendication 5, dans
lequel les au moins quatre haut-parleurs (106) sont
positionnés dans le tableau de bord (110) entre le
pare-brise (120) et un aérateur de dégivrage (118)
également positionné dans le tableau de bord (110).
15
20
7.
Système audio (100) selon la revendication 5, dans
lequel les au moins quatre haut-parleurs (106) ont
chacun un diamètre inférieur à 50 mm.
8.
Système audio (100) selon la revendication 5, dans
lequel la ligne d’agencement est une ligne unique
ayant un rayon de courbure prédéterminé.
9.
Système audio (100) selon la revendication 5, dans
lequel la ligne d’agencement est une ligne unique
ayant une pluralité de rayons de courbure prédéterminés.
10. Système audio (100) selon la revendication 5, dans
lequel la ligne d’agencement forme une ligne droite
unique.
11. Système audio (100) selon la revendication 5, dans
lequel les au moins quatre haut-parleurs (106) sont
positionnés dans le tableau de bord (110) de manière à être dirigés sensiblement verticalement et un
champ acoustique peut être formé avec une combinaison constructive d’impulsions sonores directes
provenant des haut-parleurs (106) et d’impulsions
sonores directes provenant des haut-parleurs (106),
qui sont réfléchies par le pare-brise (120).
12. Système audio (100) selon la revendication 5, dans
lequel les haut-parleurs (106) sont utilisables de manière coopérative afin de générer un champ acoustique horizontal pouvant être commandé en utilisant
une impulsion sonore directe générée par les hautparleurs (106) et chacun des haut-parleurs (106) est
également utilisable afin de générer un champ
acoustique vertical provenant de la combinaison
constructive d’une première partie de l’impulsion sonore directe et d’une impulsion sonore réfléchie,
fournie par une réflexion par le pare-brise (120)
28
25
30
35
40
45
50
55
15
13. Système audio (100) selon la revendication 5, dans
lequel les au moins quatre haut-parleurs (106) peuvent être configurés pour diriger un contenu audio
vers un premier emplacement prédéterminé et diriger également un contenu audio vers un second emplacement prédéterminé différent du premier emplacement prédéterminé.
14. Système audio (100) selon la revendication 1, comprenant un système de traitement audio (104) configuré pour diriger un premier signal audio vers une
première moitié de l’agencement linéaire (102) et un
second signal audio vers une seconde moitié de
l’agencement linéaire (102).
15. Système audio (100) selon la revendication 14, dans
lequel le premier signal audio est le signal gauche
de la stéréophonie et le second signal audio est le
signal droit de la stéréophonie.
16. Système audio (100) selon la revendication 14, dans
lequel l’agencement linéaire de haut-parleurs (102)
est un agencement linéaire unique (102) configuré
pour produire une image sonore pour un auditeur,
qui est perçue comme émanant d’un seul des hautparleurs (106), le plus proche de l’auditeur.
17. Système audio (100) selon la revendication 14, dans
lequel les haut-parleurs (106) de l’agencement linéaire de haut-parleurs (102) sont commandés par
des signaux audio qui sont retardés individuellement
pour diriger une première partie du champ acoustique produit par l’agencement linéaire (102) dans une
première direction et diriger une seconde partie du
champ acoustique produit par l’agencement linéaire
de haut-parleurs (102) dans une seconde direction.
18. Système audio (100) selon la revendication 17, dans
lequel les haut-parleurs (106) de l’agencement linéaire de haut-parleurs (102), qui sont positionnés
de manière adjacente, sont commandés de manière
à diriger des parties différentes du champ acoustique.
19. Système audio (100) selon la revendication 17, dans
lequel les haut-parleurs (106) de l’agencement linéaire de haut-parleurs (102) sont divisés en un premier groupe et un second groupe pour diriger les
première et seconde parties respectives du champ
acoustique.
20. Système audio (100) selon la revendication 14, dans
lequel l’agencement linéaire de haut-parleurs (102)
peut être configuré avec une première partie de
l’agencement linéaire de haut-parleurs (102) dirigeant un contenu audio vers un premier emplace-
29
EP 1 634 479 B1
ment prédéterminé et une seconde partie de l’agencement linéaire de haut-parleurs (102) dirigeant un
contenu audio vers un second emplacement prédéterminé.
pour annuler ledit contenu audio non inversé.
5
21. Système audio (100) selon la revendication 1, dans
lequel une pluralité de haut-parleurs (106) de l’agencement linéaire unique (102) reçoivent sélectivement des signaux audio retardés en fonction d’au
moins un paramètre modifiable associé au véhicule.
30
10
22. Système audio (100) selon la revendication 21, dans
lequel l’au moins un paramètre modifiable est un réglage que l’utilisateur peut configurer.
29. Système audio (100) selon la revendication 28, dans
lequel le contenu audio non inversé est dirigé en
utilisant un retard et dans lequel le même contenu
audio ayant été inversé a été dirigé en utilisant un
retard et le même contenu audio ayant été inversé
fait également l’objet d’un retard supplémentaire.
30. Système audio (100) selon la revendication 1, dans
lequel la combinaison constructive produit une réponse en fréquence du champ acoustique en
moyenne de moins de plus ou moins 5 dB entre 100
Hz et 10 000 Hz.
15
23. Système audio (100) selon la revendication 21, dans
lequel l’au moins un paramètre modifiable est une
indication d’un contenu audio relatif à une conversation téléphonique.
20
24. Système audio (100) selon la revendication 1, dans
lequel une pluralité de haut-parleurs (106) de l’agencement linéaire unique (102) reçoivent sélectivement un premier groupe de signaux audio retardés
lorsque le contenu audio est de la musique et un
second groupe de signaux audio retardés lorsque le
contenu audio est vocal.
25. Système audio (100) selon la revendication 1, dans
lequel une pluralité de haut-parleurs (106) de l’agencement linéaire unique (102) reçoivent des signaux
audio retardés pour diriger un contenu audio à la fois
vers un premier emplacement prédéterminé et vers
un second emplacement prédéterminé.
25
30
35
26. Système audio (100) selon la revendication 1, dans
lequel un premier groupe de haut-parleurs (106) de
l’agencement linéaire unique (102) reçoivent un signal audio retardé pour diriger un contenu audio vers
un premier emplacement prédéterminé et un second
groupe de haut-parleurs (106) de l’agencement linéaire unique (102) reçoivent un signal audio retardé
pour diriger un contenu audio vers un second emplacement prédéterminé.
31. Système audio (100) selon la revendication 1, dans
lequel l’impulsion sonore directe et l’impulsion sonore réfléchie se combinent sensiblement en phase en
raison de la proximité de haut-parleurs (106) avec
la surface réfléchissant les sons.
32. Système audio (100) selon la revendication 31, dans
lequel les haut-parleurs (106) forment un agencement linéaire unique (102) dans le tableau de bord
(110) d’un véhicule et la surface réfléchissant les
sons est le pare-brise (120) du véhicule.
33. Système audio (100) selon la revendication 32, dans
lequel les haut-parleurs (106) forment un agencement linéaire (102) ayant un rayon de courbure qui
correspond sensiblement au rayon de courbure de
la surface réfléchissant les sons.
34. Système audio (100) selon la revendication 31, dans
lequel l’agencement linéaire unique (102) est positionné dans une surface sensiblement au point vers
lequel converge l’agencement linéaire (102) avec la
surface réfléchissant les sons afin de former un angle déterminé.
40
45
27. Système audio (100) selon la revendication 26, dans
lequel chacun de haut-parleurs (106) du premier
groupe est positionné de manière adjacente à au
moins un des haut-parleurs (106) du second groupe.
35. Système audio (100) selon la revendication 31, dans
lequel ladite surface est une surface sensiblement
horizontale s’étendant longitudinalement et la surface réfléchissant les sons s’étend longitudinalement
de manière adjacente à la surface horizontale de
façon que l’agencement linéaire (102) soit positionné sensiblement parallèlement à ladite surface et
dirigé au moins partiellement vers la surface réfléchissant les sons.
50
28. Système audio (100) selon la revendication 1, dans
lequel l’agencement linéaire unique (102) peut être
configuré avec une première partie de l’agencement
linéaire unique (102) pour diriger un contenu audio
non inversé vers un emplacement prédéterminé et
une seconde partie de l’agencement linéaire unique
(102) pour diriger le même contenu audio ayant été
inversé vers un second emplacement prédéterminé
36. Système audio (100) selon la revendication 31, dans
lequel les impulsions sonores directes et l’impulsion
sonore réfléchie sont produites par un unique hautparleur de l’agencement linéaire (102).
55
37. Système audio (100) selon la revendication 31, dans
lequel sensiblement en phase signifie que le déphasage entre l’impulsion sonore directe et l’impul-
16
31
EP 1 634 479 B1
sion sonore réfléchie est inférieur à un déphasage
de 90° entre 100 Hz et 10 kHz.
5
10
15
20
25
30
35
40
45
50
55
17
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21
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22
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23
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REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader’s convenience only. It does not form part of the European
patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be
excluded and the EPO disclaims all liability in this regard.
Patent documents cited in the description
•
•
•
GB 2273847 A [0003]
US 6584202 B1 [0003]
25
EP 0481163 A2 [0003]
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