вход по аккаунту



код для вставкиСкачать
Patent Translate
Powered by EPO and Google
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a monolithic
stereo baffle. Monolithic stereo baffles are known, for example, as described in US Pat. No.
4,572,325. Such baffles do not include two sound reconstruction columns, and only one
monolithic device allows better reconstruction of the sound field or acoustic environment than
conventional devices having two baffles. In particular, these monolithic baffles allow the local
localization of good sound by the listener, ie a three-dimensional sound restoration which is
practically independent of the position of the listener relative to the baffle, while the sound
restoration is by two separate baffles or columns If not done. The disadvantages of these existing
monolithic baffles lie in acting only on reflections, meaning emitting sound waves in the direction
of the walls which are directed back towards the shack space. This has in practice on the one
hand to have an exposed wall since the entire listening room is not suitable for reflective
listening, and on the other hand the quality of the restoration is the nature of the reflecting wall,
its texture, hardness, wrinkles, modulus of elasticity Etc. as well as by the distance separating this
reflective wall from the monolithic baffle. The present invention aims at the realization of a
monolithic stereo baffle which avoids the drawbacks mentioned above while retaining the
advantages relating to the sound restoration quality obtained by the baffles described in the
above mentioned U.S. patent. The invention for that purpose forms an angle with the first group
of transducers and the first line arranged along the first line and supplied by all or part of the
"right" signal of the amplifier of the hi-fi circuit. Consisting of a second group of transducers
arranged along a second line and supplied by all or part of the "left" signal of the amplifier, said
first and second groups consisting of the same number of converters, The 300 to 1000 Hz paths
separating the active areas of the two associated transducers whose “right” and “left”
signals supplying the transducers are in phase and each belong to one of the groups Forming an
acoustic coupling with respect to said frequency between these two associated transducers, thus
being substantially equal to an odd multiple of a half wavelength of the frequency contained
between It has a baffle. In the following, embodiments of the invention will be described in
conjunction with the accompanying drawings which schematically show, by way of example,
various embodiments and variants of a human localized mode and acoustic baffle for a sound
Mainly empirical recent research can obtain physiological functions of human listening such as
sounds to be heard, noise etc. especially in the field of local limitation. From these studies, several
proofs shown in FIGS. 1 to 3 can be proposed. FIG. 1 shows that the human ear can be sensitive
to the perception of music in the range A of about 20 Hz to 20 KHz with an intensity of 20 to 93
dB. Empirically, the human ear can sense in area B, which is more restrictive, and it can not be
limited to 300 Hz -1,5 KHz; 40 dB or more, where human resonance can be localized from where
the sound comes from. It only relates to the region arising from the range C of 73 dB. This
localization is made by two parameters, namely on the one hand the time difference Δt which
separates the perception of the same-wave curve by the left and right ear, and on the other hand
the sound pressure difference Δp of the forward wave between the two ears. FIG. 2 shows that
the two parameters Δt and Δp, which allow localization of the sound, are useful in a practically
equal manner in the region centered around 1100 Hz, above this frequency It is the sound
pressure difference Δp which is dominant, while below this frequency it is the time difference
Δt which is dominant with regard to local localization of the sound. FIG. 3 shows the perception
of the acoustic audible forward wave coming from point P by the listener's left ear G and right
ear. If the left ear G listens to the fling sound at the intensity of Pl for a time t0, the right ear
listens to the sound at the time (to + Δt) and at the strength or sound pressure (p2 = p1−Δp).
On the basis of these demonstrations that the applicant has experimentally proved, the applicant
has in fact all parts of the learning room to enable the stereophonic listening to occur near the
actual listening conditions. At a frequency comprised between 300 Hz and 4 KHz and a sound
pressure comprised between 4 Q dB and 9 Q dB, the listener through the combination of left and
right signals originating from separate sources but localized in only one stereo baffle Different
positions against fi1cf! It is inferred that it is necessary to allow the reproduction of the process
parameters Δt and Δp generated during direct listening of the sound originating from the sound
source having. For a frequency range of at least 300 Hz to 40 KHz, from two microphones
separated by an average distance separating the human ear more than in providing these left and
right signals to multiple loudspeaker pairs This can be realized by recording left and right signals
by means of a listening head, each of these loudspeaker pairs can be acoustically coupled for
different frequencies.
Furthermore, the loudspeaker pairs are arranged relative to one another in a manner to form a
continuous front of the waves, taking into account the various coupling frequencies. In this way,
the listener can restore parameters that allow local localization of the sound as heard directly by
the direct listener located at the center of the listening room, almost anywhere in the listening
room. A first embodiment of a monolithic stereo baffle according to the invention according to
the above criteria is shown in perspective in FIG. This embodiment consists of a baffle having the
cross-sectional shape of a prism whose cross-section has the shape of an isosceles triangle whose
base is formed by its small sides. The other two sides 1, 2 serve as supports for the loudspeaker
groups directed respectively to one channel, right and left, each group having the same number
of loudspeakers. These two sides 1.2 and the base 3 of this baffle are connected by the front wall
4 and the back wall 5 thus forming a closed baffle. Each group of loudspeakers ° 10
forms a pair of loudspeakers separated by a different distance from one pair to the other pair of
loudspeakers 11.12 of the second group. Allows the realization of acoustic coupling of these
pairs to different frequencies, associated with 13, 14 ° 15. In the example shown, the
loudspeaker pairs 6.11 are separated by a distance corresponding to a half wavelength of the
frequency of 300 Hz. Distance b, c separating other pairs of loudspeakers. d and e correspond to
half wavelengths of the 450, 650. 950 and 2000 Hz frequencies, respectively. Thus, an acoustic
coupling is realized between these loudspeaker pairs tX 200 Hz to 3 KHz, i.e. in a frequency
range required for local localization of the sound, for a well-determined frequency which is
alternately determined. It is clear that the response characteristics of the various pairs of
loudspeakers can be matched or different. In different cases, the loudspeaker pair 6, 11 is
particularly adapted for low frequency recovery, whereas the pair 10.15 is particularly adapted
for high frequency recovery. The quality of sound restoration is highly dependent on the quality
of the loudspeakers, whereas the spatial or acoustic environment (which incorporates local
localization of the sound) mainly covers the frequency range included between 300 and 1000 fz
(Δt) It depends on the coupling between the different pairs of loudspeakers it covers. Such
monolithic stereo baffles can be placed in the middle of a sunning room and can produce good
quality stereo listening in areas X, Y such as that shown in FIG.
FIG. 5 shows a modification of this first embodiment. In this variant, at least some pairs of
loudspeakers are processed and supplied to the left and right amplifier 16.17 via a band-pass
filter 18.19, each band-pass filter 18.19fl thus supplied Choose different frequency passbands
for the pair. The passbands directed to the loudspeaker pairs are brought close to the frequency
corresponding to the half wavelength separating the loudspeakers so that this supply mode
further reinforces the acoustic coupling and thus the spreading effect of the sound restoration. It
should be noted that the effect of the local limitation depends on the wave front of the frequency
between 300 Hz and IKHz and of the pressure difference Δp between 1000 and 40 DOHz and
this local limitation is very much within 1 ms. On the contrary, the quality of musical
transmission depends on a very wide range from 20 Hz to 20 KHz and is recognized by the
human brain throughout the time interval of 1 to 3 seconds. Thus, it is possible to sufficiently
distinguish between means allowing completeness of the sound (music, noise etc.) and means
allowing localization of the sound. In the variant shown in FIG. 6, the acoustic coupling of the
loudspeakers belonging to the given pair is not made by the distances a to eiC separating the
loudspeakers through the interior of the baffle as described above, but by the exterior of the
baffle The length of the half circumferences a 'to e' corresponding to the length of the wave front
separating the loudspeakers is equal to an odd multiple of the half wavelength corresponding to
the desired coupling frequency when considering the spherical propagation of the sound wave
According to the fact. Get the bond, which is external to the baffle here. It can be envisaged to
realize a baffle in which internal as well as external coupling is realized in other embodiments.
The wave fronts generated by the various pairs of loudspeakers in the embodiment as shown in
FIG. 6 are not synchronized to the localized damage as well as the fidelity of the sound
restoration. In order to avoid this drawback, the wave fronts a 'to e' are synchronized in the plane
of symmetry of the baffle by means of the fc delay line incorporated in the supply of the
electrical signals of the loudspeaker pair, ie the waves in the plane of this plane Different time
delays can be produced for each pair of loudspeakers of the signal so that the front has a
maximum at a certain time. This coherence of sound is very important with respect to the
localization function so that this synchronization can be limited for loudspeaker pairs tuned to
frequencies contained between 300 and 1000 Hz.
In the embodiment shown in FIGS. 7-9, the baffles are arranged in groups of two loudspeakers
21 ° 22.23.24 and 25, 26. arranged along two lines forming an angle between them. 27. 28
consists of a surface baffle 20 fixed to it. The back wall of the baffle is provided with a tuning
chamber 29, 30 DEG 31.32 connecting the two groups of loudspeakers forming pairs 21-25; 2226; 23-27 and 24-28. These tuning chambers are such that they constitute a constant frequency
between 300 Hz and IKHz, for example 350 Hz, 450 Hz, 65 Q Hz and 950 Hz, so that the
resonators are for these frequencies of the corresponding loudspeaker pair Allow the binding of
This coupling gives a complete perception of local localization of the sound and thus can realize
the full spread of the sound diffusion of the baffles, with respect to the frequency of the left and
right signals with a time delay Δt and a sound pressure difference Δpk. Allow warranty. 11 and
12 show a third embodiment of a monolithic stereo baffle formed from a base 29.2 baffle 30 and
a top 31 and two end walls 32. FIG. Each baffle 30 serves as a support for a group of
loudspeakers 33.34, 35.36, 37.38 formed in pairs 33-36.34-37 and 35-38 '. In this example, the
distances a, b equal to the half wavelength corresponding to the desired coupling frequency, as
described above. Allows coupling between identical pairs of loudspeakers for different constant
frequencies (included between 300 Hz and IKHz) for each loudspeaker pair in making cf.
Furthermore, the local limitation of each group of loudspeakers arranged not only in height but
also in depth corresponds to the simultaneously emitted frequencies at which the loudspeaker
pairs are tuned in the middle plane Z-Z of the baffle The sound can be arranged to make a
common wave front 2 which further enhances the quality of sound perception and localization
ability. In the embodiment shown in FIG. 13, the baffles consist of two forward baffles 39.40
which are inclined rearward and form an angle between them. Baffles can be obtained on the
bottom, earth, back and side walls. Loudspeakers are panful 39, 4. (11) fixed to each other and
arranged to form a pair 41-42.43-44 degrees 45-46; Internal or external coupling is
implemented for a determined frequency between 300 and 1 KHz between the same pair of
loudspeakers to ensure a good recovery of the parameters defining the localization of the sound.
Furthermore, the loudspeaker groups are arranged on the buckle along a curve such that the
tonal parts of the loudspeaker pair are all arranged in the central plane of symmetry of the baffle
with respect to the tuning frequency. As we have previously found, information related to spatial
localization is only necessary in the frequency range that is included between 300 and 3000 Hz
whereas sound quality recovery is in the frequency range up to about 20,000 Hz Clearly, we can
separate these pieces of information as we need them. Therefore, an embodiment of a baffle as
shown in FIG. 14 can be realized, which baffle is a loudspeaker 47 for the low frequencies (20300 Hz) whose curved surface is supplied by the mono signal, It has a truncated pyramid shape
with a square or rectangular bottom, with loudspeakers 48 for wavenumbers (300-3,000 Hz) and
loudspeakers 49 for high frequency 'PI' (3,000-30,000 Hz). These loudspeakers 47.48 and 49
are of good quality and are they the final elements of a musical high fidelity reproduction circuit?
Configure. In addition, this baffle consists of three pairs of loudspeakers 50-51 and 52, tuned as
previously seen for frequencies of, for example, 350 Hz, 600 Hz and IKHz on its side. The
positions of these three loudspeakers are such that the wave front of the pair is synchronized to
the frequency in the plane of symmetry of the baffle. These loudspeaker pairs are supplied by a
stereo signal that delivers the information Δp and Δt = 2 in the entire listening area allowing
local localization of the sound, as has been seen before. In a variant, it is possible to have a music
channel which transmits inter-tone-limited information and a chopstick having only one spread
channel which cooperates with respect to the frequencies comprised between 300 and 4.000 Hz.
Although many embodiments and variations can be considered to obtain the best desired results,
the loudspeaker arrangement is baffled for various frequencies where the left and right
loudspeaker pairs are included between 300 Hz and IKHz. It is always necessary to obtain the
desired spread that is intended to be acoustically coupled through the inner workings and / or
the outer two. Furthermore, the quality of the restoration if arranged in such a way that the
loudspeakers are realized in the plane of symmetry of the baffles for the sound waves emitted by
different loudspeaker pairs for different frequencies to which the common wave front is coupled
In particular, for listeners who are accustomed to good left and right channel separation as
delivered by the known stereo baffles when the baffles are not supplied through the sound
recording matrix corresponding to human listening, but for example when supplied through the
multi-microphone matrix There may be provided complementary transducer pairs coupled at a
frequency of 300 to 1000 Hz and supplied by the left and right signals opposite in phase. Thus,
the action of channel separation is enhanced.
Brief description of the drawings
Fig. 1 is a schematic diagram showing the human sound part region of music and speech as a
function of sound intensity and sound frequency as well as the region where localization of the
sound source is possible, and Fig. 2 one localization of the sound source and A schematic
diagram showing the region made by the time difference and sound intensity difference between
the active parts of the other ear as a function of sound intensity and sound frequency, FIG. 3
arising from a sound source located in front of and to the left of it A schematic diagram showing
sound signals to be processed and listened to the left and right ears of a listener, FIG. 4, FIG. 5
and FIG. 6 schematically show six modifications of the first embodiment of the baffle according
to the present invention Fig. 7, Fig. 8 and Fig. 9 are schematic views showing a second
embodiment of the baffle according to the present invention, and Fig. 10 is an explanation
showing the three-dimensional listening area of the apparatus shown in Fig. 4 to Fig. Figures 11
and 12 show a third embodiment of the panful according to the invention. Schematic, FIG. 13 is a
schematic diagram showing a fourth embodiment of the baffle according to the present
invention, FIG. 14 is a schematic view showing a fifth embodiment of the baffle according to the
present invention.
In the figure, reference numeral 1, 2 龜 side of the baffle, 6 · · · base, 6-10. 11-15 · · ·
Loudspeaker, 16. 17. · · amplifier, 20 · · · flat baffle, 21-24.25 28 · · · Loudspeakers, 29-32 · · F
[room, 30 · · · baffles, 63-38 as loudspeakers, 39 · 40 · · · baffles 41 to 52 fist · loudspeakers.
Attorney Attorney Attorney Sasaki Kiyotaka (3 persons outside) 1 + +; \ 1--..
Без категории
Размер файла
18 Кб
Пожаловаться на содержимое документа