CN1165468A - Thin wall coaxial multi-layer barrel-shaped louderspeaker box with audio-frequency amplifier capable of tuning according to sound chamber - Google Patents
Thin wall coaxial multi-layer barrel-shaped louderspeaker box with audio-frequency amplifier capable of tuning according to sound chamber Download PDFInfo
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
- H04R1/22—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only
- H04R1/28—Transducer mountings or enclosures modified by provision of mechanical or acoustic impedances, e.g. resonator, damping means
- H04R1/2807—Enclosures comprising vibrating or resonating arrangements
- H04R1/2853—Enclosures comprising vibrating or resonating arrangements using an acoustic labyrinth or a transmission line
- H04R1/2857—Enclosures comprising vibrating or resonating arrangements using an acoustic labyrinth or a transmission line for loudspeaker transducers
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/04—Circuits for transducers, loudspeakers or microphones for correcting frequency response
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Abstract
A sound enclosure with cylindrical structure as sound chennal features audio couple between back radiated audio wave and surround air cluster. The cylindrical structure has inherent rigidity and bending strength, so its wall is very thin and enclosure is smaller and simpler. An amplifier turned by listening room can removes very low and narrow frequency bands from sound signals. The resonance in listening room is detected by injecting frequency-changed sound signals and detecting the sound energy peaks. The filter can remove the frequency related to resonance of listening room from sound wave signal's frequencies.
Description
The present invention relates to the low voice speaking equipment of putting, especially comprise the audio amplifier of drive access acoustical coupling and the low voice speaking equipment of putting that can be tuning according to specific acoustic surrounding.
Sound-reproducing system is constantly put equipment development to better quality is low voice speaking.Just, by research and development, the what is called that acoustic energy changes because of wave length of sound " unintentional nonlinearity is useless " constantly improves.From the playback that records sound of sound, the huge improvement on equipment quality is of value to discriminating audience.Unfortunately, for most of audio frequency apparatus, the work of being studied still rests within the scope of distortion and frequency response, particularly at low frequency or bass wavelength.Even state-of-the-art equipment is also pursued the linear playback effect of sound blindly at the extremely low frequency place.
High-quality music sound wave from the diaphragm of loudspeaker is coupled to listening room by the acoustics rule, and corresponding anti-phase sound wave then comes from the back side of the diaphragm of loudspeaker.This back radiative acoustic wave in the time of in the air mass around finally being coupled to, has just been introduced non-linear effect in the high-quality ambient sound that the previous irradiation sound wave is provided.The method that solves makes progress, but the improvement of sound matter is always not matched with respect to cost.
Traditional cone-shaped diaphragm loud speaker is released audio amplifier with air, produces sound wave in listening room.Sound wave from the diaphragm of loudspeaker front and the back side is complementary, just differs from 180 ° on phase place.Therefore, in same listening room,,, can in sound effective value, introduce non-linear owing to the interference and the counteracting of sound wave towards previous irradiation and the coupling of the sound wave of radiation backward.Theoretically, if so back radiative acoustic wave is coupled to independently listening room, just can avoid the interference and the counteracting of sound wave; For example, the diaphragm of loudspeaker is being installed within the walls, is being sent the previous irradiation sound wave, sending the back radiative acoustic wave to second listening room to first listening room.Unfortunately, Fu Za wall fixedly speaker system can not realize most of audiences.
The device of traditional transmission sound effective value is a loud speaker that is placed in the audio amplifier in listening room.Direct and the listening room coupling of the front surface of the diaphragm of loudspeaker, the inner couplings of its back side and casing.Unfortunately, low voice speaking the releasing of high tone quality must be with the audio amplifier perforate or the discharging of back radiative acoustic wave, and just, the sound wave of back radiation must finally spread out of casing.The back radiative acoustic wave that spreads out of in casing is preferably introduced less or is not introduced any interference and counteracting with respect to the previous irradiation sound wave.
Sound drive access radiative acoustic wave after the audio amplifier inner control.Usually, the drive access audio amplifier provides acoustical coupling by the rear surface of the diaphragm of loudspeaker to listening room along the chamber in drive access or given length or cross section.The length of sound drive access is that the wavelength with specific frequency of sound wave changes, as the resonance frequency of loud speaker.Cross section is then corresponding to the effective surface area of sound source, as, the effective surface area of the diaphragm of loudspeaker.
Known have multiple sound drive access loud speaker and commercial be valuable.Regrettably, owing in most of drive access loud speaker, need very long cavity length, to adapt to the very sound wave of low frequency, so the drive access loud speaker has developed into very big and very heavy structure.In audio amplifier, the sound drive access can be arranged by the mode in labyrinth is folding, to set up needed length in overall audio amplifier as box form.Dividing plate is typically wooden plate, forms needed sound drive access or have the chamber of suitable cross section in case.Be the distortion of the sheet material that prevents to be caused by acoustic pressure in the sound drive access, these plates must be that enough structural strengths are arranged, i.e. thickness is to keep the rigidity of anti-wave pressure.In audio amplifier, thick plate structure is combined to form as folding labyrinth type sound drive access, and the result has produced complexity and the very big audio amplifier of volume.
Main purpose of the present invention provides a kind of drive access audio amplifier, and it has the sound drive access of suitable length and cross section, and does not need very big volume and complicated loudspeaker box structure.
By around wall, floor and the reverberation sound wave that produces of ceiling, in listening room, also bring and other sound wave between interference.This interference is introduced non-linear in the another kind of high tone quality sound that loud speaker provided.Acoustic absorption material in listening room and meticulous tuning scheme are tried hard to so non-linear minimum that reduces to, and still such method and apparatus always can not improve tonequality pro rata with needed cost.
Cavity resonance effect in listening room has produced the effective reverberation that reduces the high tone quality sound effective value and has interfered the source.The cavity resonance effect of chamber is a resonance on given fundamental frequency and the relevant harmonic frequency.For general typical room size, the fundamental frequency of resonance frequency all drops in the frequency range that can listen.Because the existence of cavity resonance effect, the acoustic energy of fundamental frequency are easy to consume unlike other frequency.On fundamental frequency and harmonic frequency, generate and set up acoustic pressure therefrom.So the auditor just feels on fundamental frequency and corresponding harmonic frequency relative higher sound is arranged.In other words, in a given listening room; The acoustic pressure of being set up on fundamental frequency and harmonic frequency is tending towards too high, protrudes in the outer annoying noise of linear sound effective value and become for discriminating hearer.
In addition, the cavity resonance frequency that listening room had changes along with atmospheric density, furnishings or barometric information.In a given listening room, to predict that very narrow cavity resonance frequency band is impossible.In some listening room, the cavity resonance frequency band may be that 1Hz (hertz) is narrow like that.In addition, because fundamental frequency and the very narrow and uncertain characteristic of harmonic band predict that the plan that prevents with these very narrow Base Bands of filtering is impracticable.
An object of the present invention is to provide a kind of apparatus and method that are used for eliminating from sound effective value cavity resonance at the sound playback time.
According to one embodiment of present invention, a kind of drive access audio amplifier comprises the speaker driving apparatus fixed position that limits fore-and-aft direction.One first cylindrical shell that is provided with respect to the loud speaker fixed position receiving the back radiative acoustic wave in first termination, and is broadcasted the back radiative acoustic wave at second end.One coaxial with first cylindrical shell and around it relative again second cylindrical shell greater than first cylindrical shell.Be used to guide back radiative acoustic wave from first cylindrical shell to enter space between first and second cylindrical shells at a lid of second cylindrical shell, second end.
Can under coaxial situation, increase other additional cylindrical shell.The increase of each cylindrical shell radius sets up that it is own and near a space between its inner barrel, and this space has a cross section that equates with the central tube cross section, i.e. the needed cross section of drive access loud speaker.The cylindrical shell variable-length is to determine needed sound drive access length.
Drive access audio amplifier of the present invention generally includes the sleeve of a plurality of coaxial arrangements.A sleeve in bosom has been determined the relevant sound space of a given cross section.Remaining each sleeve is determined one relevant space with immediate between than small sleeve it self.The cross section in each relevant sound space equates with given cross section.Lid between sleeve and the sleeve connects its marginal portion in case, set up one by the sound space and say drive access.
Be according to a further aspect in the invention, a kind of sound-reproducing system listening room tuning part receives a voice signal, and provides a filtered acoustical signal.This tuning part comprises that one can be applicable to the variable-frequency of listening room and comprises the sound source of a frequency-indicating device.One vocal input transducer is measured and the interior acoustic energy of indication listening room.One filter receives acoustical signal and provides filtered acoustical signal.This filter comprises at least one control part, with the frequency band of the filtering of calling the roll of the contestants in athletic events, and this frequency band is demarcated with frequency-indicating device.In a single day peak value in the acoustic energy will indicate the cavity resonance frequency that will control in filter as long as enter within the frequency range that comprises listening room cavity resonance frequency.
A kind of sound system of the present invention is carried out tuning method to listening room, begins by the cavity resonance frequency that detects listening room, adjusts filter then to detected resonance frequency, with the acoustical signal of filtering on resonance frequency.Thereafter, this method is added to this sound with filtered acoustical signal and listens indoor acoustical convertor.
Main contents of the present invention at length provide and propose respectively claim at the lower part of this specification.Yet, to structure of the present invention and method of operation and other advantage and purpose,, can get the best understanding by with reference to the following description that combines with accompanying drawing, parts identical among the figure adopt identical label.
For a better understanding of the present invention, and show exploitativeness of the present invention,, now accompanying drawing is illustrated by the mode of embodiment.
Fig. 1 is the schematic diagram of coaxial many tubulars drive access audio amplifier of the present invention.
Fig. 2 is that the sound drive access that provides of Fig. 1 audio amplifier is along the cross-sectional view of 2-2 crosscut among Fig. 1.
Fig. 3 is the cutaway view of Fig. 1 audio amplifier 2-2 along the line.
Fig. 4 is the second embodiment schematic diagram of coaxial many tubulars drive access audio amplifier of the present invention.
Fig. 5 is the cross-sectional view of audio amplifier shown in Figure 4 along Fig. 4 line 5-5.
Fig. 6 is the more detailed structure schematic diagram of Fig. 1 audio amplifier.
Fig. 7 be by first embodiment of the invention can be tuning according to given listening room an analog audio amplifier.
Fig. 8 be by second embodiment of the invention can be tuning according to given listening room a digital audio amplifier.
Fig. 1 has provided the schematic diagram of one three sound drive access audio amplifiers 10.Audio amplifier 10 has a roof 14 outwardly, and sidewall 26 and bottom opening 27, (driving) device 12 of raising one's voice is installed on the roof 14.Sound wave 16 before loud speaker 12 sends promptly, makes progress and back sound wave 18 outwardly with respect to audio amplifier 10.Back sound wave 18 transmits in audio amplifier 10, and finally spreads out of from bottom opening 27.Central cylinder 20 is settled with the spigot shaft coaxle ground of case 10.The upper end 20a of central cylinder 20 is ring flange 24 shapes, radially extends to the sidewall 26 of case 10 and opens.Back sound wave 18 is along the upper surface 24a path of ring flange 24, and footpath upper port 12a enters the space 21 in the central tube 20.The lower end 20b of central tube 20 keeps opening.
Radius greater than second cylindrical shell 30 of central tube 20 also with central shaft 22 coaxial arrangements.Therefore, central tube 20 general coaxial being arranged within second.Upper end 20a and ring flange 24 exceed the upper end 30a of second cylindrical shell 30, and extend towards loud speaker 12.The circumference of the upper end 30a of second cylindrical shell 30 keeps opening.One lid 32 covers the lower end 30b of second cylindrical shell 30, but the open lower end 20b of decentre tube 20 has a given distance.Along with back sound wave 18 propagates and spread out of lower end 20b downwards in the space 21 of cylindrical shell 20, sound wave 18 final bumps cover 32 inner surface 32a.Lid 32a guiding is from the space 31 of sound wave 18 to second cylindrical shells 30 in the tube 20.Especially, covering 32 direct sound waves 18 enters the space between inner core 20 and the urceolus 30 and is prolonging space 31 to up.As shown in Figure 1, inner surface 32a comprises the core of a projection and recessed peripheral part.Such shape profile can enter second cylindrical shell, 30 needed path of navigation from central cylinder 20 according to sound wave 18 and accurately set with mathematical method.In addition, lid 32 must be suitably spaced apart with the end 20b of tube 20, to keep needed cross section from transmit in space 21 to space 31.
In either case, sidewall 26 limits a space 29 between the inner surface of second cylindrical shell, 30 outer surfaces and sidewall 26.Space 29 is opened to listening room by casing 10 bottom openings 27.As the upper end 30a that sound wave 18 is propagated by second cylindrical shell 30, the lower surface 24b of sound wave 18 bump ring flanges 24.Lower surface 24b reverse leading sound wave 18 is downward along the inner surface of sidewall 26, just, enters in the space 29 between second cylindrical shell and the sidewall 26.Sound wave 18 is finally gushed out from the bottom opening 27 of casing 10.Leg 40 is connected with sidewall 26, and at opening 27 with lay between the floor 42 of casing 10 and reserve a gap.
Fig. 2 has provided the cross section of casing 10 interior spaces 21,31 and 29, and has provided identical sound drive access cross-sectional area.The cross section in space 21 is circular, and corresponding to effective displacement area of loud speaker 12.The cross section in space 31 promptly between cylindrical shell 20 and cylindrical shell 30, is annular and equates with the cross-sectional area in space 21.Space 29 also has a cross section that equates with space 21 and 31.And the annular cross section in space 29 is to produce to form the cylindrical portion that sidewall 26 adopts, and then adopts a structure with " half four directions " shape in this specific embodiment of the present invention.
Fig. 3 shows the structural representation of the casing 10 that provides along Fig. 2 center line 2-2, and has provided careful " half four directions " shape by sidewall 26.In Fig. 3, form by outer wall 26, the shape of " half four directions " cross section is limited by a cylindrical shell 60.Cylindrical shell 60 is by four each " half four directions " shapes that 22 four parallel parts 62 form in the axis.Each several part is limited by a dull and stereotyped wall 64 that is connected with adjacent part 63 that cylindrical shell 60 is kept.Additional twisted plate 66 that enough resistances to bending are arranged on the inner surface of each dull and stereotyped wall 64.In this mode, twisted plate 66 has been introduced enough resistances to bending for another piece surface plate 64.Still shown in Fig. 3, twisted plate 66 is attached on the outside of cylindrical shell 30 at fulcrum 70 places, so that assist to support the combination of cylindrical shell 20 and 30.In addition, support arm 72 connects the outer surface of cylindrical shell 20 and the inner surface of cylindrical shell 30, further to help support structure and rigidity.
Therefore, casing 10 provides a sound drive access, and back sound wave 18 is coupled in casing 10 air chamber outward.Following formula has calculated the sound drive access (L) that changes with wave length of sound (λ):
L＝λ/4
Except length, the sound drive access must provide the cross-sectional area that is equal to its sound wave that transmits along its path, that is, in fact the cross section with loud speaker 12 equates.Loud speaker manufacturer usually with the given effective displacement area of a given loud speaker as its calibration value.By correctly selecting the radius of each tube structure, long along whole sound drive access, produce the cross section of an equalization.
Here, corresponding to the interior cross-sectional area A1 of the central tube 20 of the displacement area of loud speaker 12.Below formula for being that central tube 20 inner surfaces of benchmark are asked radius with axle center 22:
Woofer can be the scope at six inches to 12 inches.For these loud speakers, cylindrical shell 20 and 30 wall thickness may diminish to the aluminum of 0.5-1.5 millimeters thick.Though extremely thin, such structure is strong to being enough to the anti-vibration deformation that is impacted initiation by acoustic pressure wherein.Same result promptly uses plastic material, also can obtain very thin wall thickness.
The use of aluminium and plastics is compared in traditional material that is substituted such as timber in manufacturing coaxial many tubulars sound drive access, and tube has been changed production.In addition, but the recycling of aluminium and plastic material is according with one's environment of another derivation of the present invention and ecological characteristics.For example, an aluminum cylinder can be compared with plank formation pipe.For the aluminum cylinder of the wall thickness of 300 millimeters interior diameters and 0.5 millimeter, under two atmospheric pressure, radial deformation is about 0.14 millimeter.Have identical in cross section as a wooden pipe of 266 square millimeters, need about 12 millimeters wall thickness just can bear two atmospheric pressure and produce 0.18 millimeter displacement.Therefore, under the approximately uniform resistance to deformation condition, tubular construction allows to use extremely thin wall, that is to say in corresponding to gas pressure, and the pipe that plank constitutes has the wall thickness more about 24 times than aluminum cylinder wall thickness.
The outer radius of cylindrical shell 20, promptly inside radius adds cylindrical shell 20 wall thickness, can be set at R
1, the inside radius of second cylindrical shell 30 can be calculated by following formula:
Second cylindrical shell, 30 wall thickness consider that used material determines a needed resistance to bending.The outer radius of second cylindrical shell 30 can be set at R
2, the inside radius of next coaxial cylindrical shell can calculate with following formula:
With previous cylindrical shell outer radius is benchmark, can increase any amount of additional cylindrical shell with suitable inside radius, and cross section equates with loud speaker 12 effective surface areas to keep therebetween.The cylindrical shell of one right quantity and cylindrical shell length form needed sound drive access length in audio amplifier.
With lid 32 and ring flange 24 direct sound waves from a cylindrical shell to the process of next cylindrical shell, must keep the cross-sectional area of appointment.Correspondingly, the specific dimensions of these structures and shape, as cover 32 and ring flange 24, can be designed to make sound wave 18 on transfer path, to keep such cross section.
Fig. 4 has provided and has comprised that inline coaxial cylindrical shell forms the schematic diagram of the second embodiment of the present invention of a drive access audio amplifier 100.In Fig. 4, casing 100 comprise one with the spatial relationship on floor 142 are the bowl-shaped bodies 114 that support in leg 140 modes.Bowl-shaped body 114 is as the fixed position of loud speaker 112.Previous irradiation sound wave 116 from loud speaker sends out by bowl- shaped body 114 and 142 centres, floor.Audio amplifier 100 comprises a top central opening 127.Loud speaker 112 produces a back radiative acoustic wave 118.Sound wave 118 is propagated in casing 100, flows out casing 100 at last at top central opening 127 places, just, flows to definite opening 127 places of central tube from outer cylinder body and sends out.
Central cylinder 120 directly is placed in the top of loud speaker 112, and has determined top central opening 127 in its upper end.One second cylindrical shell 122 bigger than cylindrical shell 120 radiuses settled coaxially with cylindrical shell 120.One settles with cylindrical shell 120 and 122 coaxially than cylindrical shell 122 the 3rd big cylindrical shells 124 on diameter.One diameter is provided with cylindrical shell 120,122 and 124 coaxially greater than the 4th cylindrical shell 126 of cylindrical shell 124.One radius is settled with cylindrical shell 126,124,122 and 120 coaxially greater than the lateral wall cylindrical shell 128 of cylindrical shell 124.Lateral wall cylindrical shell 128 is directly connected in bowl-shaped body 114 with its lower limb, and is supported by bowl-shaped body 114.Coaxial cylindrical shell 120,122,124,126 and 128 combination are remained on fixing pass by the mode of inline support component 130 and fasten, and can well find out among Fig. 5.
A space 121 has been determined in the inside of cylindrical shell 120.A space 123 has been determined in the inside of the outer cylinder body 122 of cylindrical shell 120.A space 125 is determined in the inside of the outer cylinder body 124 of cylindrical shell 122.A space 129 is determined in the inside of the outer cylinder body 128 of cylindrical shell 126.Cylindrical shell 120,124 and 128 extends to more than beyond cylindrical shell 122 and 126.
One ring cover 150 is on the apical margin of cylindrical shell 124 and 128.Equally, ring cover 152 is on the apical margin of cylindrical shell 120 and 124.Do more comprehensively explanation below, 129 direct sound waves 118 enter space 127 from the space for lid 150.Same, 125 direct sound waves 118 enter space 123 from the space for lid 152.Lid 154 comprises that the core of a projection and recessed marginal portion live the lower end closed of cylindrical shell 122.123 direct sound waves 118 enter space 121 from the space to cover the concavo-convex profile of 154 inner surfaces.Can recognize that lid 154 must be from the enough at interval distances of cylindrical shell 120, so that acoustic wave propagation path keeps needed cross-sectional area.Ring cover 156 is across the root edge of cylindrical shell 126 and 122, thereby 127 direct sound waves 118 enter space 125 from the space.
As discussed above, the length of the drive access that is provided in the casing 100, can by with to cover the control of the overall length dimension that 150,152,154 and 156 separately cylindrical shells 120,122,124,126 and 128 combine, obtain adjusting to satisfy certain wavelengths.The relative spacing of lid 150,152,154 and 156 and 120,122,124,126 and 128 of relevant cylindrical shells must consider to keep the needed cross-sectional area that provides along drive access casing 100.Also have, relative size, promptly cylindrical shell 120,122,124,126 and 128 radius be by the front describe obtain so that space 121,122,123,125,127 and 129 keeps the cross-sectional area of equivalent size.
Fig. 6 has provided the more detailed structure of the audio amplifier of Fig. 1-3 illustrated embodiment.In Fig. 6, audio amplifier 10 ' be to provide in the cross section mode, be similar to cross-sectional view shown in Figure 3.Casing 10 ' be provided with one 8 inches loud speakers (not shown among Fig. 6)." half four directions " shape that discussed casing 10 ' be set at front.Horizontal and vertical the two width is 280 millimeters in Fig. 6 diagrammatic sketch.Casing 10 ' height be to determine by selected drive access length, that is, and with a specific wavelength of surrounding air group Best Coupling be functional relation.That lateral wall 26 has is recited above " half four directions " shape of cross section, thick is 1.5 millimeters.Interior wall construction, promptly cylindrical shell 20 and cylindrical shell 30 only have 0.5 millimeters thick.Cylindrical shell 20 has 87.50 millimeters radius, and cylindrical shell 30 has 125.00 millimeters radius.For the radius of the cylinder 60 of " half four directions " type formation base of sidewall 26 is 165.00 millimeters.Twisted plate 66 is thick to be 1.5 millimeters, and their sweep is to extend to have on the camber lines 150 that 116.00 millimeters radiuses and angle of release are 51.39 degree.Casing 10 ' fillet, i.e. the reserve part of cylindrical shell 60 is that extending at angle of release is on the camber lines 152 of 26.09 degree.
4 support arms 72 that distribute, radially extend along the circumference isogonism of casing 10 ' also be included in.Especially, support arm 72b links a fillet of cylindrical shell 30 and sidewall 26, and support arm 72a links cylindrical shell 20 and cylindrical shell 30.Similarly, support arm 72c and 72d radially outwardly to casing 10 ' next fillet extend, support arm 72c links cylindrical shell 20 and cylindrical shell 30, and support arm 72d links cylindrical shell 30 and sidewall 26.Support arm 72e and 72f similarly with respect to casing 10 ' the 3rd fillet setting.At last, support arm 72g and 72g in the same way to external radiation extend to casing 10 ' last fillet.
Like this, just provided and described one improved the drive access audio amplifier.Audio amplifier of the present invention utilizes the intrinsic rigidity and the high anti-bending force of tubular construction, chooses the sound drive access of length and cross-sectional area by coaxial relation formation therebetween.Coaxial many cylindrical arrangement can the simplified design method, to set up needed length and cross section; And the direction of the quantity of the position of limiting loudspeaker, required cylindrical shell or acoustic emission not.The audio amplifier that the present invention provides in light weight, saved the space with the material that can reuse.The sound wave of back radiation both can be arranged to from outer cylinder body and move to central cylinder, also can be arranged to from central cylinder and move to outer cylinder body.
Here explanation is as cylinder simultaneously, and other similar tube-in-tube structure has intrinsic high anti-bending force, and can be used as more satisfactory tube-in-tube structure, i.e. the branch of cylindrical sleeve.For example outer wall 126 constitutes the tube-in-tube structure with " half four directions " shape cross section among Fig. 1 embodiment.
Here the audio amplifier that illustrates has the ability of the very pure low-frequency sound wave of generation.The conventional loud speaker pure like this low-frequency sound wave of generally can not resetting.Thereby, use this coaxial many tubulars audio amplifier to introduce the new field of sound reproduction, promptly produce the ability of very pure bass.The generation of pure like this low-frequency sound wave is the needed characteristic of discriminating audience, and this very pure low-frequency sound wave can form a kind of effect that echoes in listening room.In other words, low-frequency sound wave has been reproduced in said here audio amplifier loyalty fully, to cause that in general audition cavity echoes.
Fig. 7 has provided the block diagram of the sound-reproducing system 210 that is positioned at a given listening room or chamber 212.Can recognize that listening room or chamber 212 have a given cavity resonance frequency that comprises fundamental frequency and relevant harmonic frequency.System 210 comprises a sound source 214, and sound source 214 is delivered to a buffer amplifier 218 with the right side and left tone channel 216a and 216b.Buffer amplifier 218 amplifies tone channel 216 and tone channel 216 is delivered to one group of variable ratio frequency changer notch filter 220 of connecting, and uses filter 220a here respectively, and 220b and 220c represent.For example, notch filter 220 is variable or tunable so that each notch filter has a narrow frequency band and a high rejection ratio characteristic.For example, on the frequency of the 30Hz left and right sides, each filter 220 provides 1 or from 1 to 1.5Hz wide " swallow " or filtering band.Each filter 220 comprises that three are adjusted synchronous variable resistors, and is tunable in the adjustable notch filter filter of narrow-band very to become.
Each filter 220 receives tone channel 216a and 216b, and filtering is very narrow and a wavelength that frequency is low wherein.And offer next contiguous unit as output tone channel 216a and 216b.Filter 220a receives tone channel 216a and 216b from buffering amplifier 218, and carries tone channel 216a and 216b to notch filter 220b.Filter 220b carries tone channel 216a and 216b to filter 220c, and filter 220c carries tone channel 216a and 216b to an equalization filter 230.Each notch filter 220a-220c comprises a corresponding control knob 222a-222c respectively, to control wavelength filtered from tone channel 216a and 216b.
Sound wave 240 enters chamber 212, and provides desired sound effective value according to sound source 214.Yet because the resonance effect that chamber 212 exists, some part of sound wave 240 is tending towards forming and sending the stronger volume of preparing to express than sound source 214 of volume and experiences.Particularly, in chamber 212, be tending towards producing some very low-frequency sound wave.
Here, system 210 carries out conventional operation in the mode of conventional sound-reproducing system, but has all comprised the notch filter of a series of very narrow-bands, so that utilize the control of control knob 222 that the narrow low-frequency band of selecting among tone channel 216a and the 216b is eliminated.
According to the present invention, system 210 also comprises a 20Hz to 20KHz (kilohertz) sine wave signal generator 250, and it provides a sine wave 252 to be input in the output driver 232.Signal generator 250 comprises the frequency of a control knob 250a in order to specification signal 252.The frequency-indicating device 254 that is connected to signal generator 250 can intuitively show the frequency of signal 252.Thereby by manual operation control knob 250a, the user of system 250 just can inject a given frequency sound wave 240 in chamber 212.
When in case control knob 250a adjusts to fundamental frequency with sound wave 240, user's observed frequency indicating device 254.Frequency-indicating device 254 is chamber 212 its fundamental frequencies of demonstration so.The user adjusts one of them notch filter 220 then, promptly adjusts its control knob 222, so that consistent with the frequency values of indicating device 254 demonstrations.Can recognize that given scale is corresponding on control knob 250a and control knob 222, can make the user set control knob 222 so that be complementary with it under these circumstances according to the setting of control knob 250a.Another kind of situation is, the information that control knob 222 can provide by frequency-indicating device 254 and calibrated scale in addition.In a word, one in the notch filter 220 is to be used to adjust to a certain given frequency band, and this frequency band is the sine wave freuqency according to being injected into chamber 212, can provide a relatively large acoustic energy to set.The user adopts this mode to eliminate a narrow-band of sending in the sound source 214.
Other frequency band, promptly harmonic frequency also can be introduced undesirable non-linear in sound effective value.Such harmonic frequency also can be further observation by manual operation control knob 250a and acoustic energy display 264 detect.If the user observes other crest frequency, i.e. the peak value that on acoustic energy display 264, shows, other several notch filters 220 can be used for the corresponding narrow-band of filtering so.Can recognize, in the embodiment that the present invention provides, can use greater or less than three notch filters 220.
Frequency suppresses, and promptly uses notch filter 220 filtering, generally is used in below the 250Hz.In the frequency more than 250Hz, the reverberation interference fringe is very wide, and equalization filter 230 can be used to purify any such broad-band interference frequency.Yet, be very low and narrow frequency band because chamber resonance relates to, traditional equalization filter can not be eliminated chamber resonance rightly.
Fig. 8 shows the second embodiment of the present invention, one provide more automatically be tuned to the digital system 310 of the given chamber 312 humorous frequencies method of shaking.In Fig. 8, digital sound source 314 provides digital audio signal 316, and it includes the right side and leftstereophonic channel, to a digital signal adjusting part 318.Digital signal adjusting part 318 excitations one variable parameter digital filter 320.Can recognize that digital filter is subjected to applying the control of parameter, one or more frequency filter functions of selecting with formation.Digital filter 320 output drives, one D/A converter and driver 332.Driver 332 provides an analog signal 316 of amplifying, and represents with 316a, to output transducer 340, promptly arrives as previously described coaxial many tubulars audio amplifier, and the right side of acknowledge(ment) signal 316a and L channel.
As described earlier, system 310 is operation under conventional digital sound is reset generally, but regulates the variable parameter digital filter 320 of having connected between part 318 and the driver 332 in digital signal.
The course of work of parameter setting and control section 350 operand word filters 320.Parameter is set control section 350 receiving frequency signals 352 harmony level signals 354.Frequency signal 352 is from sine-wave generator 356, by frequency counting with read part 358 and arrive this part.Also have, the output of sine-wave generator 356 is applied to digital signal and regulates part 318 as exchanging sound source.In this case, the sound wave of a selected frequency injects in system 310 in chamber 312.
One input converter, promptly microphone 360 is monitored the sound wave in the chambers 312 and is driven an amplifier 362.Amplifier 362 drives a vocal level assembly 364.Vocal level assembly 364 transmits acoustic energy signal 354 and sets and control assembly 350 to parameter.Microphone 360 can be arranged on the select location in the chamber 312, i.e. the LisPos an of the best is to form desirable acoustic surrounding at this selected LisPos.
System 310 is that benchmark is promptly set with chamber 312 given environment by a given chamber condition of resonance, and by at first initial to the sine wave signal of a slow frequency conversion of chamber 312 injections.Transducer 360 receives sound wave and provides reproduction sound to vocal level assembly 364 by amplifier 362.Parameter is set and control assembly monitoring chambers 350 312 interior expressions detect the signal 354 of acoustic energy size, and detects the peak value in the signal 354.
The peak value that parameter is set and control assembly 350 will show in signal 354 connects with the given frequency in frequency signal 352, thereby is chamber 312 detection chambers resonance frequencys.Then parameter set and control assembly 350 in digital filter 320, set up a pair of should be in the frequency parameter of detected chamber 312 resonance.Such process can repeat, to detect other peak value vocal level reading and relevant frequency values in chamber 312.In this case, one or more frequency parameters are added to digital filter 320, with filtering from signal 316 and the relevant narrow-band of chamber 312 resonance.
After initial period, system 310 is with the mode operand word sound source 314 of routine, but with adjustable parameter digital filter 320 the detected narrow-band relevant with chamber 312 resonance eliminated.Thereby playback system 310 is tuned on the particular cavity resonance of chamber 312.Can recognize so tuningly also can cause the change of indoor environment by the user artificially.
So far, provided a kind of improved sound-reproducing system, and described have be tuned to the ability of particular chamber resonance.Improved audio amplifier of the present invention can produce very low and level and smooth low-frequency sound wave signal, comprising the very narrow low-frequency band relevant with chamber resonance.Frequency such in the acoustical signal had been carried out filtering before improved audio amplifier is broadcasted.In this case, acoustical signal is " pre-decay " on the frequency corresponding to the chamber resonance frequency, thereby has eliminated the indoor rapid collection of sound that changes with chamber resonance.Thereby discriminating hearer likes enjoying the more real linear replaying effect as the sort of sound of desire performance in the former recording.
Be appreciated that to the invention is not restricted to illustrate and illustrated specific embodiment, can make in the claim under not exceeding and the scope of equivalents and change variation.
Claims (20)
1. sound drive access audio amplifier is characterized in that comprising:
The loud speaker of a definite fore-and-aft direction is settled the position;
One first cylindrical shell, it is settled the position with respect to described loud speaker and is provided with, and with radiative acoustic wave after receiving in first termination, and broadcasts described back radiative acoustic wave at second end;
One second cylindrical shell, it is coaxial and relatively greater than first cylindrical shell with described first cylindrical shell, the inside radius of described second cylindrical shell is that the outer radius by described first cylindrical shell is that benchmark is selected, so that in fact the cross-sectional area that forms between described first and second cylindrical shells equates with the interior cross-sectional area of described first cylindrical shell, first end of described second cylindrical shell is adjacent with first end of described first cylindrical shell, and second end of described second cylindrical shell is adjacent with second end of described first cylindrical shell;
Described second end that lid is positioned at described second cylindrical shell enters described space between described first and second cylindrical shells with guiding from the back radiative acoustic wave of described first cylindrical shell, keeps the cross-sectional area that equates in fact with described space simultaneously.
2. sound drive access audio amplifier according to claim 1 is characterized in that the pattern length of described first and second cylindrical shells is consistent with given sound drive access length.
3. sound drive access audio amplifier according to claim 1 is characterized in that also comprising:
One around the sleeve of described second cylindrical shell, and described sleeve comprises adjacent to one first end of described first end of described second cylindrical shell with adjacent to one second end of described second end of described second cylindrical shell; One guide plate, it links described first end of described first cylindrical shell and described first end of described sleeve, and it is spaced apart with described first end of described second cylindrical shell, so that described guide plate is guided out described second cylindrical shell with described back radiative acoustic wave, and sends into the space between described second cylindrical shell and described sleeve.
4. sound drive access audio amplifier according to claim 3 is characterized in that the cross section of described sleeve is defined as half square, and described sleeve comprises the planar wall part, and described audio amplifier also comprises the supporting walls of the resistance to bending that increases described planar wall part.
5. sound drive access audio amplifier according to claim 3 is characterized in that the space cross-sectional area between described second cylinder and the described sleeve is consistent with the cross-sectional area of described first cylindrical shell.
6. sound drive access audio amplifier according to claim 1 is characterized in that also comprising an opening that is coupled to described first end of described second cylindrical shell with sound.
7. a sound transmits the passage audio amplifier, it is characterized in that comprising:
The sleeve of a plurality of coaxial settings, determined a sound space of being correlated with in the sleeve at the center in the described sleeve, and has a given cross-sectional area, each remaining sleeve it self with described sleeve in determine one relevant space than it between little No. one sleeve, the cross-sectional area in each described space equates with described given cross-sectional area in fact;
A plurality of lids are used to link the edge of described each sleeve, to form one drive access by described sound space in described audio amplifier.
8. sound according to claim 7 drive access audio amplifier, it is characterized in that described sound transmit passage comprise the sound space of the sleeve in described center in the described sleeve transaudient to the sound space of the relevant outermost of outermost of described sleeve.
9. sound drive access audio amplifier according to claim 7 is characterized in that when loud speaker is installed to described audio amplifier the described sound space of described cylindrical central sleeve at first receives the back radiative acoustic wave of loud speaker.
10. sound-reproducing system listening room tuning block, it receives a voice signal and provides the voice signal of a filtering, it is characterized in that described tuning block comprises:
A variable ratio frequency changer sound source that can be applicable to described listening room, and comprise a frequency-indicating device;
A vocal input transducer of in described listening room, measuring and indicating acoustic energy;
One receive described acoustical signal and provide filtering after the filter of acoustical signal, described filter comprises a control knob at least, it is called the roll of the contestants in athletic events by the frequency band of described filter filtering, and is that benchmark is demarcated by described frequency-indicating device.
11. tuning block according to claim 10 is characterized in that described filter is a notch filter.
12. tuning block according to claim 10 is characterized in that described filter is a tunable notch filter.
13. tuning block according to claim 11 is characterized in that described filter is the digital variable parametric filter.
14. filter according to claim 10 is characterized in that: described filter comprises a plurality of control knobs, each filtered band of calling the roll of the contestants in athletic events, and described each control knob is that benchmark is demarcated with described frequency-indicating device.
15. tuning block according to claim 10 is characterized in that described variable ratio frequency changer sound source is variable sine wave freuqency sound source.
16. the method for a tuning listening room audio system is characterized in that this method comprises following step:
Detect the chamber resonance frequency of described listening room;
Adjust filter to described detected resonance frequency, with the acoustical signal of the described resonance frequency of filtering;
The acoustical signal of filtering is applied to described indoor sonic transducer.
17. method according to claim 16 is characterized in that described detection step comprises the steps:
Inject variable sound wave to described chamber;
Monitor described indoor peak value acoustic energy level;
When the frequency of sound wave that injects is relevant with described peak value acoustic energy level, identify described chamber resonance frequency.
18. method according to claim 16 is characterized in that described step is self-adjusting step, wherein said detection step automatically enters into one provides the step of described detected resonance frequency to get on.
19. harmony method according to claim 16 is characterized in that the step of adjusting filter comprises the adjusting notch filter.
20. one kind can is characterized in that this system comprises by the tuning sound-reproducing system of listening room:
One provides the sound source of first acoustical signal;
At least one variable ratio frequency changer notch filter, described notch filter comprise a control knob in order to the filtered band of calling the roll of the contestants in athletic events, and described notch filter receives described first acoustical signal, and it is fulfiled the frequency filtering function, and provide a filtered acoustical signal;
One second sound source, it provides a rising tone signal as the variable ratio frequency changer acoustical signal;
One acoustical convertor is used to receive an acoustical signal of amplifying, and injects corresponding sound wave to listening room;
One acoustic driver is used to receive the acoustical signal and the described rising tone signal of described filtering, thereby described system is tuning to listening room, before this in a frequency range to the described rising tone signal of indoor injection, monitor that described acoustic energy level device is to determine listening room cavity resonance frequency, and with the expression value of described resonance frequency as control to described notch filter, so the acoustical signal of described filtering is added in the described listening room goes, to get rid of described various resonance frequency.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US08/600,304 | 1996-02-12 | ||
| US08/600,304 US5920633A (en) | 1996-02-12 | 1996-02-12 | Thin-wall multi-concentric cylinder speaker enclosure with audio amplifier tunable to listening room |
| FR9701549A FR2759526A1 (en) | 1996-02-12 | 1997-02-11 | Transmission line loudspeaker enclosure for use with tunable audio reproduction equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1165468A true CN1165468A (en) | 1997-11-19 |
Family
ID=26233314
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN97101922.3A Pending CN1165468A (en) | 1996-02-12 | 1997-02-12 | Thin wall coaxial multi-layer barrel-shaped louderspeaker box with audio-frequency amplifier capable of tuning according to sound chamber |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPH1028299A (en) |
| CN (1) | CN1165468A (en) |
| FR (1) | FR2759526A1 (en) |
| GB (1) | GB2310104A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102480662A (en) * | 2010-11-24 | 2012-05-30 | 单志渊 | Sound box |
| CN113271508A (en) * | 2020-02-17 | 2021-08-17 | 东莞宝德电子有限公司 | Annular radiation sound box structure |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7184556B1 (en) | 1999-08-11 | 2007-02-27 | Microsoft Corporation | Compensation system and method for sound reproduction |
| CN101883304B (en) * | 1999-08-11 | 2013-12-25 | 微软公司 | Compensation system for sound reproduction |
| CN2842944Y (en) * | 2005-10-27 | 2006-11-29 | 方书哲 | Novel column loudspeaker |
| KR100963560B1 (en) * | 2009-07-24 | 2010-06-15 | 범진아이엔디(주) | Speaker |
| WO2011138468A1 (en) * | 2010-05-03 | 2011-11-10 | Moreton Cesteros Angel Julio | Acoustic enclosure for loudspeakers |
| DE102012109002B4 (en) * | 2012-09-24 | 2017-11-02 | Kienle Orgeln GmbH | Resonator sound radiation system |
| JP6593741B2 (en) * | 2014-04-30 | 2019-10-23 | パナソニックＩｐマネジメント株式会社 | Speaker system |
| JP6590637B2 (en) * | 2015-10-28 | 2019-10-16 | Dmg森精機株式会社 | Speaker device |
| GB2553603A (en) * | 2016-08-09 | 2018-03-14 | Studio17 Design Ltd | Loudspeaker |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB337264A (en) * | 1929-12-13 | 1930-10-30 | Celestion Ltd | Improvements relating to acoustic instruments |
| GB656732A (en) * | 1949-04-21 | 1951-08-29 | John Forrester | Improvements in or relating to loud speakers |
| US4168761A (en) * | 1976-09-03 | 1979-09-25 | George Pappanikolaou | Symmetrical air friction enclosure for speakers |
| FR2433879A1 (en) * | 1978-08-16 | 1980-03-14 | Launay Dominique | UNIDIRECTIONAL ACOUSTIC SPEAKER |
| JPS58190114A (en) * | 1982-04-28 | 1983-11-07 | Koden Electronics Co Ltd | Variable narrow band stop filter |
| US5245665A (en) * | 1990-06-13 | 1993-09-14 | Sabine Musical Manufacturing Company, Inc. | Method and apparatus for adaptive audio resonant frequency filtering |
| KR930006651B1 (en) * | 1991-01-30 | 1993-07-22 | 삼성전자 주식회사 | Automatic level control circuit for sound |
| JP2941573B2 (en) * | 1992-07-21 | 1999-08-25 | 松下電器産業株式会社 | Narrow band stop filter |
| GB9407221D0 (en) * | 1994-04-12 | 1994-06-08 | Hilpus Indrek | A loudspeaker |
-
1997
- 1997-01-10 GB GB9700453A patent/GB2310104A/en not_active Withdrawn
- 1997-02-11 FR FR9701549A patent/FR2759526A1/en active Pending
- 1997-02-12 JP JP9028075A patent/JPH1028299A/en active Pending
- 1997-02-12 CN CN97101922.3A patent/CN1165468A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102480662A (en) * | 2010-11-24 | 2012-05-30 | 单志渊 | Sound box |
| CN113271508A (en) * | 2020-02-17 | 2021-08-17 | 东莞宝德电子有限公司 | Annular radiation sound box structure |
| CN113271508B (en) * | 2020-02-17 | 2022-08-12 | 东莞宝德电子有限公司 | Annular radiation sound box structure |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH1028299A (en) | 1998-01-27 |
| GB9700453D0 (en) | 1997-02-26 |
| GB2310104A (en) | 1997-08-13 |
| FR2759526A1 (en) | 1998-08-14 |
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