sls音箱線陣廠方培訓(xùn)ppt課件

1、RBA - 1線陣列揚(yáng)聲器原理PrinciplesofLine ArraysR Bob AdamsInternational DirectorrbobSLSaudiorbobadamsSLS AUDIOOzark, MissouriSLSaudio線陣列是一種揚(yáng)聲器單元的陣列方式，它可以對(duì)聲音進(jìn)展良好的控制，并在產(chǎn)生反響之前提供適當(dāng)?shù)脑鲆?。Line Arrays have been recognized as a loudspeaker design that can provide excellent control and gain before feedback.為了合理得當(dāng)?shù)剡\(yùn)用線陣列

2、揚(yáng)聲器，設(shè)計(jì)者必需明確揚(yáng)聲器設(shè)計(jì)和操作的一些根本原理。To properly use Line Arrays, the designer must understand some basic principals of loudspeaker design and operation.為了合理得當(dāng)?shù)剡\(yùn)用線陣列揚(yáng)聲器，設(shè)計(jì)者必需明確揚(yáng)聲器設(shè)計(jì)和操作的一些根本原理。To properly use Line Arrays, the designer must understand some basic principals of loudspeaker design and operation.線陣

3、列揚(yáng)聲器 Line Arrays早期的線陣列揚(yáng)聲器 Early Line Array規(guī)范的揚(yáng)聲器構(gòu)造Standard Loudspeaker Construction規(guī)范的揚(yáng)聲器是點(diǎn)聲源Standard Loudspeakers arePOINT SOURCEdevices規(guī)范的揚(yáng)聲器構(gòu)造Standard Loudspeaker Construction點(diǎn)聲源的聲學(xué)特性POINT SOURCE characteristics 球面波輻射 Spherical wave propagation Spherical = 球狀 聲波傳播以三維的方式進(jìn)展 Waves spread in 3 dimens

4、ions規(guī)范的揚(yáng)聲器構(gòu)造Standard Loudspeaker Construction球面波的輻射特性Spherical Wave Propagation點(diǎn)聲源的聲學(xué)特性 POINT SOURCE characteristics 聲波以三維的方傳播 Waves spread in 3 dimensions 當(dāng)間隔添加一倍時(shí)，由于間隔產(chǎn)生的損耗 = -6 dB Loss over Distance = -6 dB per doubling of distance 這就是所謂的平方反比定律Know as the Inverse Square Law 損耗dB = 20*LOG Dft/3.28

5、LossdB = 20*LOG Dft/3.28 規(guī)范的揚(yáng)聲器構(gòu)造Standard Loudspeaker Construction數(shù)學(xué)的根本原理The Mathematic Fundamentals實(shí)際上的點(diǎn)聲源： A theoretical point source: 2 X 半徑 R = 4 X 面積 2 X the radius R = 4 X the area4 X 面積 = 能量, 或 6 dB 聲壓級(jí)損失 4 X the area = power, or a 6 dB loss of level因此，平方反比定律為：間隔每添加一倍損失6dB Thus the inverse-sq

6、uare law: 6dB per doubling of distanceCourtesy of Ulysses Line Array Research平方反比定律 Inverse Square Law 普通系統(tǒng) Conventional Systems規(guī)范的揚(yáng)聲器構(gòu)造Standard Loudspeaker Construction普通系統(tǒng)聲壓級(jí)以dB計(jì)Conventional SystemSPL in dB100941248丈量點(diǎn) Measurement Points8288線陣列的特性Line Array Characteristics 柱面波輻射 Cylindrical wave p

7、ropagation 柱體 Cylinder = 縱向的 Strait forward projection 聲波以二維的方式傳播 Waves spread in only 2 dimensions線陣列利用聲波干涉原理加強(qiáng)或減弱來(lái)限制聲波的輻射角度Line Arrays use the physics of interference effects (summation and cancellation) to restrict wave spreading 線陣列 Line Array柱面波cylindrical wave 線陣列的特性Line Array Characteristics

8、柱面波輻射 Cylindrical wave propagation 當(dāng)間隔每添加一倍時(shí)，間隔所呵斥的損耗=-3dB Less Loss over Distance =-3 dB per doubling of distance只適用于近場(chǎng) Near Field only數(shù)學(xué)的根本原理The Mathematic Fundamentals實(shí)際上的無(wú)限線聲源 A theoretical infinite line-source: 2 X 半徑 R = 2 X 面積 2 X the radius R = 2 X the area2 X 面積 = 能量, 或 3dB 的聲壓級(jí)損失 2 X the a

9、rea = power, or a 3dB loss of level因此，無(wú)限點(diǎn)聲源在間隔添加一倍時(shí)，只損耗3dB Thus infinite line sources loose only 3dB per doubling of distanceCourtesy of Ulysses Line Array Research平方反比定律Inverse Square Law 線陣列系統(tǒng)Line Array Systems線陣列系統(tǒng)聲壓級(jí)以dB計(jì)Line Array SystemSPL in dB丈量點(diǎn)Measurement Points1248100979491線陣列系統(tǒng)聲壓級(jí)以dB計(jì)Line

10、 Array SystemSPL in dB1248100979491普通系統(tǒng)聲級(jí)以dB計(jì)Conventional SystemSPL in dB100888294平方反比定律Inverse Square Law比較 Comparison線陣列的特征Line Array Characteristics間隔每添加一倍，間隔引起的損耗=-3dBLess Loss over Distance =-3 dB per doubling of distance只適用于近場(chǎng)Near Field only一個(gè)設(shè)計(jì)者如何決議線陣列的近場(chǎng)或遠(yuǎn)端場(chǎng)呢？How does a designer determine th

11、e Near Field or Far Field of a Line Array?例：Example線陣列 Line array = 4m高 4m tall近場(chǎng)DNear Field (D) = 25米 25 meters近場(chǎng) NEAR Field-3 dB SPL 損耗-3 dB SPL loss遠(yuǎn)場(chǎng) FAR Field-6 dB SPL 損耗-6 dB SPL lossD=L2f/636近場(chǎng)/遠(yuǎn)場(chǎng)的概念 Near Field / Far Field Concept一切有限線聲源在一定間隔后會(huì)轉(zhuǎn)變?yōu)辄c(diǎn)聲源All finite line-sources transition into poi

12、nt-sources at some distance我們把這個(gè)轉(zhuǎn)變間隔稱(chēng)作該線聲源的臨界間隔We will call the center of this transition area a line sources Critical Distance這是由于在遠(yuǎn)間隔的聽(tīng)眾看來(lái)， 聲源更像是一個(gè)點(diǎn)而不是線This is because the size of the source, from the perspective of the distant listener, is more similar to a point than a line數(shù)學(xué)的根本原理The Mathematic

13、FundamentalsFresnel vs. Fraunhofer 近場(chǎng)和遠(yuǎn)場(chǎng)的比較near-field vs. far-field數(shù)學(xué)的根本原理The Mathematic Fundamentals根本線陣列揚(yáng)聲器頻率耦合的幾何學(xué)Basic Line Array Geometryfor Frequency Coupling根本線陣列揚(yáng)聲器頻率耦合的幾何學(xué)Basic Line Array Geometry for Frequency CouplingPLH最大耦合波長(zhǎng) H Highest coupling HL = 陣列長(zhǎng)度 Length of the arrayH = 兩個(gè)單元聲中心的間隔

14、 Center to Center spacingP = 換能器件的直徑 Piston (transducer) diameter = 頻帶寬度 Bandwidth最大耦合波長(zhǎng) H Highest coupling H為了合理地耦合一切超越5kHz的頻率，換能器件必需小于2.676.8cmTo properly couple any frequency above 5 kHz,the transducers must be spaced less than 2.67 (6.8 cm) 這對(duì)實(shí)踐設(shè)計(jì)來(lái)說(shuō)是完全不現(xiàn)實(shí)的Completely unrealistic for a practical d

15、esign線陣列假設(shè)建立在一堆簡(jiǎn)易揚(yáng)聲驅(qū)動(dòng)單元的堆砌上，是不能夠在高頻下作為線聲源運(yùn)用的 NO line array, based on a simple stack of cone drivers, can perform as a line source at high frequencies垂直1米長(zhǎng)的帶有一組4 間隔驅(qū)動(dòng)單元的線陣列Vertical polars of a 1-meter line array with a 4 driver spacing4 間隔 = 3384Hz，所以大致看來(lái)，1600Hz 的驅(qū)動(dòng)間隔大約為 ，3150Hz 大約為 1 ，6300Hz 大約為 2 .

16、4 spacing = of 3384 Hz, so at roughly 1600 Hz the driversare apart, at 3150 Hz they are 1 apart, and at 6300 Hz they are 2 apart在1 的圖里，在第一對(duì)突起處，高階的傾斜分支出如今軸向的上方和下方At 1, the first pair of prominent, high-level gradient lobesappear above and below the main lobe1600 Hz( )3150 Hz(1 )6300 Hz(2 )線陣列未被適當(dāng)耦合的情

17、況Line Array - not properly coupled輻射不延續(xù) Dispersion inconsistent聲壓級(jí)分布不規(guī)律 SPL irregularity線陣列Line Array近場(chǎng)計(jì)算的數(shù)學(xué)原理Heavy Math for Near Field calculation以下公式可以算出線聲源的最低頻率：To find lowest frequency at which line source behavior will be found:F = C/H2xRR = (FxH2)/C以下公式可以算出線聲源轉(zhuǎn)化為點(diǎn)聲源的間隔：To find transition dista

18、nce from line source to point source behavior:Where:F 代表頻率 F is frequencyC 代表聲音的傳播速度 C is speed of soundH 代表陣列的高度英尺 H is array height in feetR 代表間隔 R is distance 如何決議必要的陣列高度How to determine the Necessary array height取決于以下各量組成的矩陣： Based upon a matrix of: 豎直的覆蓋角 Vertical coverage 傳播間隔 Throw distance 傳

19、播環(huán)境的混響特性 Reverberation 陣列地點(diǎn) Array location 聽(tīng)眾位置的最低點(diǎn) Lowest listener position 聽(tīng)眾位置的最高點(diǎn) Highest listener position 豎直的覆蓋角 Vertical Coverage線陣列必需可以“看到每個(gè)聽(tīng)眾位置，并且用無(wú)妨礙的“投射傳播聲音。The line array must be able to “see each listener position, and project sound with an unobstructed line of “throw.如何決議必要的陣列高度How to

20、determine the Necessary array height 豎直的覆蓋角 Vertical Coverage最低的聽(tīng)眾位置Lowest Listener Position聽(tīng)眾的最高位置Highest Listener Position陣列的位置Array Location如何決議必要的陣列高度How to determine the Necessary array height 投射間隔Throw Distance陣列位置Array location間隔最遠(yuǎn)聽(tīng)眾位置的間隔 Distance to farthest listener position根本的概測(cè)法：線陣列必需有足夠的

21、高度來(lái)保證將柱形波傳送到投射間隔的 處。General Rule of Thumb - the line array must be tall enough to produce a cylindrical waves for of the throw distance如何決議必要的陣列高度How to determine the Necessary array height普通來(lái)說(shuō)，為了保證柱面波，陣列的高度必需大致是所要求最低頻率高度的6倍。In general terms, the height of the array must be approximately 6 times the

22、 height of the desired lowest frequency to maintain cylindrical waves留意：這只是陣列的近場(chǎng)，普通是陣列高度的6倍。NOTE: This is only the NEAR FIELD of the Array, generally considered to be six times the array height.如何估計(jì)一個(gè)線陣列的投射間隔：How to estimate throw distance for a line array:計(jì)算所需求的最低頻率Determine the lowest frequency ne

23、eded for the application.1130 頻率 = 波長(zhǎng)1130 frequency = Wavelength (WL)波長(zhǎng)乘以6可以算出陣列的高度Multiply the wavelength by 6 to get the height of the array波長(zhǎng) x 6 = 高度WL x 6 = Height (H)高度乘以6可以算出近場(chǎng)的投射間隔Multiply the height of the array by 6 to get the estimated throw distance for the NEAR FIELDH x 6 =陣列的近場(chǎng)投射間隔H x

24、6 = throw distance (D) of the NEAR FIELD of the array例子Example500Hz近場(chǎng)估計(jì)的投射間隔Throw distance estimate for 500hz near field 計(jì)算運(yùn)用所需的最低頻率Determine the lowest frequency needed for the application.波長(zhǎng)乘以6可以算出陣列的高度Multiply the wavelength by 6 to get the height of the array1130 (344.42 m) 500 = 2.26 ft (.69 m)

25、 WL2.26 ft (.69 m) WL x 6 = 13.56 ft (4.16 m) H例子Example陣列高度乘以6可以算出近場(chǎng)的估計(jì)投射間隔Multiply the height of the array by 6 to get the estimated throw distance for the NEAR FIELD2.26 ft (.69 m) WL x 6 = 13.56 ft (4.16 m) H13.56 ft (4.16 m) H x 6 = 81 ft (21.7 m)4.16m 陣列的近場(chǎng)the NEAR FIELD of the 4.16m array81 f

26、t (21.7 m)混響對(duì)陣列高度的影響Impact of Reverberationon array height概算法 A Rule of Thumb混響對(duì)陣列高度的影響Impact of Reverberationon array height對(duì)于混響時(shí)間 2 秒的空間for rooms with reverb 5秒的空間或者在室外for rooms with reverb 5 seconds or outdoors投射間隔 / 2/ 3 = 陣列的高度 (D/2) / 3 = H概算法 A Rule of Thumb混響對(duì)陣列高度的影響Impact of Reverberationon

27、 array height例子Example空間聲音反射 = 3.5秒Room Reverberation = 3.5 seconds目的投射間隔 = 188ft57mTarget throw distance = 188 ft (57m) 188 / 2 = 94 94ft / 2 = 47ft 47ft / 4.5 = 10.44ft (3.2m) tall = H2 LS8695 = 9ft (2.74m)對(duì)于混響時(shí)間在2-5秒之間的空f(shuō)or rooms with reverb 2 5 seconds投射間隔/2/ 4.5 = 陣列的高度 (D/2) / 4.5 = H4000Hz200

28、0Hz500Hz250Hz31.5 Hz = 85.5 ft. 250 Hz = 30 ft. 2 kHz = 11 ft. 16 kHz = 4 ft.對(duì)一個(gè)100英尺的臨界間隔，所需求的陣列長(zhǎng)度：Length of Array needed for a 100-Foot Critical Distance010203040506070809085.4560.4242.9030.3321.4515.1710.727.585.363.7931.5 Hz63 Hz125 Hz250 Hz500 Hz1 kHz2 kHz4 kHz8 kHz16 kHz頻率赫茲 Frequency in Hertz

29、 (Log Scale)Length of Array in Feet陣列的長(zhǎng)度英尺例子 Example例子 Example對(duì)一個(gè)300英尺的臨界間隔，所需求的陣列長(zhǎng)度：Length of Array needed for a 300-Foot Critical Distance頻率赫茲 Frequency in Hertz (Log Scale)Length of Array in Feet陣列的長(zhǎng)度英尺148.00104.6574.3052.5437.1526.2718.5713.139.296.5702040608010012014016031.5 Hz63 Hz125 Hz250 Hz

30、500 Hz1 kHz2 kHz4 kHz8 kHz16 kHz31.5 Hz = 148 ft. 250 Hz = 52.5 ft. 2 kHz = 18.5 ft. 16 kHz = 6.5 ft.Break混響場(chǎng)下的線陣列Line Arrays in Reverberant Spaces混響場(chǎng)下的線陣列Line Arrays in Reverberant Spaces實(shí)踐的和估算的混響時(shí)間RT60Real vs. Apparent Reverberation (RT60) 混響時(shí)間是用點(diǎn)聲源進(jìn)展丈量和估計(jì)的 Reverberation Time is typically measured

31、 (and predicted) using spherical devices對(duì)線陣列揚(yáng)聲系統(tǒng)而言，堅(jiān)持其低頻性能的穩(wěn)定性是很重要的For line array systems, it is important to maintain consistent line array behaviorat low frequencies.以上觀念在混響場(chǎng)中尤為重要especially in very live rooms!混響場(chǎng)下的線陣列Line Arrays in Reverberant SpacesLive room with a point source混響場(chǎng)下的線陣列Line Arrays

32、 in Reverberant Spaces5000hz6只 RLA3陣列5000Hz 具有良好的垂直控制范圍6 Box RLA3 array- achieves good vertical control at 5000hz5000Hz混響場(chǎng)下的線陣列Line Arrays in Reverberant Spaces250hz5000hz250Hz在 250Hz 的時(shí)候陣列的輻射范圍幾乎是球狀的However, at 250Hz the array is almost spherical混響場(chǎng)下的線陣列Line Arrays in Reverberant Spaces一個(gè)真正擔(dān)憂(yōu)的問(wèn)題 不平

33、衡的混響聲A real concern unbalanced reverberation 混響場(chǎng)下的線陣列Line Arrays in Reverberant Spaces一個(gè)真正擔(dān)憂(yōu)的問(wèn)題 不平衡的混響聲A real concern unbalanced reverberation 假設(shè)柱面波的傳播只需在高頻的時(shí)候被控制 那么產(chǎn)生 估算的RT60“ 的聲音能量也只能影響高頻。 If spherical spreading is only controlled in the high frequencies the sound energy that produces the “apparen

34、t “RT60 is also only affecting the high frequencies!STOP54混響場(chǎng)內(nèi)的線陣列Line Arrays in Reverberant Spaces一個(gè)真正擔(dān)憂(yōu)的問(wèn)題不平衡的混響聲A real concern unbalanced reverberation *假設(shè)柱面波的傳播只需在高頻的時(shí)候被控制那么產(chǎn)生估算的RT60“的聲音能量也只能影響高頻。 * If spherical spreading is only controlled in the high frequencies the sound energy that produces

35、the “apparent “RT60 is also only affecting the high frequencies!整個(gè)房間聽(tīng)起來(lái)會(huì)“嗡嗡作響The Room will sound “boomy!55混響場(chǎng)里的線陣列Line Arrays in Reverberant Spaces在一個(gè)帶有中等大小線陣列的混響場(chǎng)里L(fēng)ive room with a mid-size Line Array564m(13.5)高的陣列 500hz4 m (13.5) tall array500hz留意沒(méi)有傳播Notice no spreading實(shí)例 Example 線陣列 Line Array574m

36、(13.5)高的陣列 250hz4 m (13.5) tall array250hz留意沒(méi)有傳播Notice no spreading實(shí)例 Example線陣列 Line Array58陣列的中心點(diǎn)必需堅(jiān)持足夠近的間隔，來(lái)保證高的一致性。Center-to-center spacing MUST be close enough to maintain coherence at high frequencies.這取決于運(yùn)用。THIS IS APPLICATION DEPENDENT謹(jǐn)記 Remember線陣列 Line Array592000Hz單個(gè)點(diǎn)聲源w/ 55.8mm (2.2) 中心點(diǎn)

37、間距Single Point source w/ 55.8mm (2.2) center-to-center spacing 建立一個(gè)線聲源Building a Line Source602000Hz2000Hz兩個(gè)點(diǎn)聲源 w/ 55.8mm 中心點(diǎn)間距Two Point sources w/ 55.8mm (2.2) center-to-center spacing 建立一個(gè)線聲源Building a Line Source612000Hz2000Hz三個(gè)點(diǎn)聲源w/ 55.8mm (2.2) 中心點(diǎn)間距Three Point sources w/ 55.8mm (2.2) center-to

38、-center spacing 建立一個(gè)線聲源Building a Line Source622000Hz2000Hz四個(gè)點(diǎn)聲源w/ 55.8mm (2.2) 中心點(diǎn)間距Four Point sources w/ 55.8mm (2.2) center-to-center spacing 建立一個(gè)線聲源Building a Line Source632000Hz1.12m (44)沒(méi)有波長(zhǎng)傳播No wave spreading2000Hz四個(gè)點(diǎn)聲源w/ 55.8mm (2.2) 中心點(diǎn)間距Five Point sources w/ 55.8mm (2.2) center-to-center s

39、pacing 建立一個(gè)線聲源Building a Line Source642000Hz1.12m (44)沒(méi)有波長(zhǎng)傳播No wave spreading2000Hz這看起來(lái)很好，但是，當(dāng)頻率比中心點(diǎn)間距還小的時(shí)候會(huì)出現(xiàn)什么呢？This looks OK BUT, what happens at frequencies smaller than the center spacing?建立一個(gè)線聲源Building a Line Source656300Hz問(wèn)題 - 大問(wèn)題Problems Big Problems6300Hz線陣列Line Array66帶有帶狀驅(qū)動(dòng)單元的換能器with Rib

40、bon TransducersPLH在同一個(gè)時(shí)間點(diǎn)在每個(gè)平面上再生的一切頻率All frequencies reproduced on each plane at the Same time傳感器之間的間隔更加小了Much shorter distance between transducers傳感器之間的頻率耦合更高M(jìn)uch higher frequency coupling between transducers相位關(guān)系得到極大提升Greatly improved Phase relationships67帶狀的換能器有著宏大的優(yōu)勢(shì)Ribbon Transducers have a eno

41、rmous advantage over the competition由于有等相位的特質(zhì)due to isophasic properties68只需一個(gè)輻射銜接平面波的平的矩形驅(qū)動(dòng)單元被密集地放置在一同時(shí)，可以結(jié)合為一個(gè)真正的線聲源系統(tǒng)ONLY a flat rectangular piston Radiating a coherent planar waveSpaced tightly together Can be combined intoA TRUE line source system69合理耦合的聲音輻射Properly coupled dispersion延續(xù)的，可控的Con

42、sistent and Controlled陣列的位置Array Location 座位的位置SeatingLocations70Proper Loudspeakers是一個(gè)線陣列Is it a Line Array ?還是只是“堆砌的音箱？Is it just “stacked upLoudspeakers ?還是orfor Line Arrays71平面陣列 和仿真 Planar Array vs. Emulation72Two compression driversWith sectored waveguidesHigh frequency planarRibbon line source堆疊的音箱Stacked upLoudspeakersThree compression driversWith small aperture longWaveguides三個(gè)緊縮驅(qū)動(dòng)單元Three Compression Drivers73Two compression driversWith