THXHT2TranslatedVersion.ppt

1,THX Professional Certification Home Theater 2 THX专业认证 家庭影院第2级,Guangzhou, China 中国广州 December 2008 2008年12月,2,Housekeeping 课堂纪律,Please turn cell phones to off or buzz 请将手机关闭或切换至振动状态 We assume you now know basic audio and video 我们假设今天来上课的学员都具备基本的影音知识 There are no dumb questions but please keep on track (mostly) 欢迎提问，但请不要离题,3,Topics - Day One 授课内容-第1天,Room Design 房间设计 Shape and Size 形状与尺寸 Reflected Sound Control 反射声的控制 Noise Control 噪声控制 Isolation 隔声 Lighting and control 灯光和中控 Room Finishes 房间内装饰 Seating 座椅,Topics Day One 授课内容第1天,Video System 视频系统 Display Size 显示设备的尺寸 Display Technologies 视频显像技术 Audio System 音频系统 Speaker Placement 扬声器摆位 Speaker Type 扬声器类型 Automation 中控系统 Business Considerations 商业要素,THX Confidential 4,Topics Day Two 授课内容第2天,System Hookup 系统连接 System Setup 系统设置 System Verification 系统检验 Mechanical 物理连接 Electrical 电子信号 System Calibration 系统调试,THX Confidential 5,6,The THX Goal THX设计目标,Totally involve the client in the story being presented 让观众完全融入到电影的故事情节当中 Just as it was created in the studio 观众所感受到的音画效果等同于电影后期工作室 Free from distraction and fatigue 完全排除所有干扰元素，彻底消除观看疲劳 At every seat 每个位置都是“皇帝位” Regardless of price 无论预算的高低，都应当在设计时充分考虑以上所有因素,7,The Solution 解决方案,Replicate the critical elements of the studio environment as much as the budget and decorator will allow 在预算和室内装修条件允许的前提下，尽可能多地复制电影后期制作室内的每一项重要元素,8,The Reference 参考标准,The standard of quality: Film studio screening rooms (not your local multiplex) 质量标准：电影公司的审片室（不是你家附近的多厅影院） Quality defined by dozens of international standards and industry best practices 质量标准的确定来源于多项国际标准和最佳工业实践,Stag Theatre, Skywalker Ranch,9,Ambience & Foley,Elements,100,000+ Pieces 超过10万条声音片段,Dialogue 对白,Music 音乐,Sound Effects 声音效果素材,Pre-Mix 前期混音,Dialogue,Effects A,DME Pre-Mix DME前期混音,Multi-channel Print Master 多声道混音,Effects B,Music Left,Music Center,Copyright THX Ltd,Music Right,Music,Left Surround,Right,Channel,Left,Channel,Center,Channel,Surround L,Channel,Surround R,Channel,Music,Right Surround,LFE,Surround Back,10,Layout of a Movie Theater: 电影院平面图,3 Screen speakers（三只银幕扬声器） Left Center Right 3 Surround arrays （三组环绕声场） Left Side Right Side Rear Subwoofers (bass managed) 超低音扬声器（低音管理） All seats face screen 所有座位都面对银幕 Good sight and sound lines 良好的视线和声线 Screen size is 0.93x seating distance (45º optimum) 银幕宽度=0.93x座位与银幕的距离（ 45º最佳） THX Screen size front to back (36º - 52º) THX银幕水平视角，从后排到前排(36º - 52º),11,Layout of a Post Production Stage: 电影后期工作室平面图,3 Screen speakers（三只银幕扬声器） Left Center Right 3 Surround arrays （三组环绕声场） Left Side Right Side Rear Subwoofers (bass managed) 超低音扬声器（低音管理） All seats face screen 所有座位都面对银幕 Good sight and sound lines 良好的视线和声线 Screen size is 0.93x seating distance (45º optimum) 银幕宽度=0.93x座位与银幕的距离（ 45º最佳）,12,Layout of a Home Theater: 家庭影院平面图,3 Screen speakers 3只银幕扬声器 3 Surround channels 3路环绕声道 Subwoofers 超低音扬声器 All seats face screen 所有座位都面对屏幕 Good sightlines 良好的视线 Screen size is 28º - 52º (40º optimum) depending on many variables 水平视角为28º - 52º (40º 最佳），实际尺寸取决于很多因素,13,Performance Goals of Home Theatre Audio 家庭影院的性能标准音频,Dialog clarity and articulation 对白清晰度和准确度 Precise sound localization 精确的声音定位 Smooth sound movement 平滑的声像移动 Spacious surround 极具空间感的环绕声场 Smooth tonal balance 平衡的音色 Tight bass 快速紧凑的低频表现 Full dynamics 宽广的动态范围 Every seat a good seat 每个位置都是皇帝位,14,Room Basics 房间设计基础知识,Stick to rectangular shapes. 长方形的房间是最佳选择 Other shapes can work, but are difficult to predict and control. 其他形状的房间并无大碍，但很难对房间内的各种声学参数进行预测和控制 Stick to rectangular rooms! 始终选择长方形房间！ Squares Not great 正方形不理想 Circles, Ovals Trouble! 圆形, 椭圆形相当麻烦！ Bay windows, more trouble! 碰到房间里有凸窗就更麻烦了！,15,Room Basics 房间设计基础知识,Room orientation 房间定向 Favor the length direction 以房间的长边方向为基准 Not too long and narrow! 不要太长也不要太窄！ 1.3 : 1 is good! Several obstacles （设计会遇到的一些挑战） Fireplace （壁炉） Windows（窗户） Doors（门） Etc.（等等）,16,The Room Basics 房间设计基础知识,Good Sound isolation 良好的隔声 No background noise 超低背景噪声 No rattles 没有共振现象 No distractions 排除所有干扰元素,17,The Room Basics 房间设计基础知识,Control sound reflections 控制声音反射 Absorption 吸收 Diffusion 扩散 Control echoes 控制回声 Absorption or Diffusion 吸收或者扩散 Reflected sound decay 反射声衰减 Target times using the right absorption 使用正确的吸音材料能达到目标时间,18,The Room Basics 房间设计基础知识,Speaker locations optimized for quality 优选扬声器的位置以确保音质 “Sound lines” Everyone should hear good sound without obstructions “声线”每位观众都能听到声音而不被阻隔 Good room acoustic design means all seats have good sound 良好的房间声学设计意味着房间内的每一个座位都有上佳的声音表现,19,Designing The Room 房间设计,It all starts with acoustics 首先考虑的是声学设计 Why talk about acoustics? 为何讨论声学？ Acoustics are audible! 房间声学效果的好坏是可以听出来的！ Controls 50% of quality or more 决定声音质量的各种因素中，房间声学效果的比例占到50%甚至更多 Acoustics are fixable 房间内的声学问题是可以解决的 Fixing acoustics can bring in $ 解决声学问题能使你赚很多钱,20,What is Acoustics? 什么是声学?,Its about the speaker/room/listener interface 是扬声器/房间/观众三者之间的一种相互关联 Its what separates great rooms from loud rooms 声学特性良好的房间和非常响的房间是有区别的 It is what you hear from 20Hz to 2kHz (not 20kHz) 声学设计关注20Hz-2KHz频带范围(请注意不是20KHz) Below 200Hz it is all room 200Hz以下的声音都是房间所产生的,21,The Acoustic Interface 声学界面,Take control of the acoustic interface 控制声学界面 Electronics Interface is under control 控制电子界面,22,The Acoustical Engineering Process 声学工程设计的流程,Dimension the room 房间尺寸 Sound isolation 隔声 Noise control 背景噪音控制 Vibration control 振动控制 Model decay time 衰减时间 Determine absorption area 确定吸音区域,Determine diffusion area 确定扩散区域 Determine treatment locations 确定需要处理的具体位置 Treat echoes 处理回声 Place listener 确定观众的位置 Place speakers and subs 扬声器和超低音选位 Tune it all 综合调试,23,Performance Goals of Home Theatre - Video 家庭影院视频设计目标,Sharpness 清晰度 Size (visual angle) 屏幕尺寸(水平视角) Brightness 亮度 Contrast (from black to white) 对比度 Color accuracy 颜色还原准确性 No artifacts 没有”伪像” Every seat a good seat 每个位置都是”皇帝位”,24,Designing the Room 房间设计,Standing Waves 驻波,25,Standing Waves = Bass Modes = Room Modes 驻波=低频共振模式=房间模式,Standing waves happen when room dimension is equal to sound wavelength 当房间的尺寸和声波波长相同时将产生驻波现象 Also at 0.5, 1.5, 2, 2.5, 3, etc. times wavelength 同样，当房间尺寸等于声波波长的0.5, 1.5, 2, 2.5, 3倍时也将产生驻波,Loudspeaker,Listener,26,After reflection, signal nulls overlap 声波在房间各块墙面多次反射后信号零点重合,Standing Waves 驻波,27,Standing Waves 驻波,All rooms have some standing waves 所有房间会产生驻波 Resonance frequencies are set by room dimensions 共振频率是由房间尺寸所决定的,Resonance overlaps depend on ratios in room dimensions Length/Width/Height 共振频率的迭加与否取决于房间的长宽高尺寸,Low Relative Pressure 声压较低区域,Low Relative Pressure 声压较低区域,Standing Waves - A Second Harmonic Length Axial Standing Wave 驻波长度轴向的二次谐波,Low Relative Pressure,Low Relative Pressure,Standing Waves Avoid Frequency overlaps 驻波避免共振频率叠加,30,Standing Waves 驻波,Standing waves cause 驻波将导致： Resonances 共振现象 Uneven frequency response 不平坦的房间频率响应 Poor bass impact 低频拖泥带水 Different bass at each seat 每个座位的低频效果都不同 Most problems are in the 30 Hz to 200 Hz range 问题一般出在30-200Hz的频率区间,Standing Waves 驻波,All rooms will have some standing waves 所有房间都会产生驻波 Resonance overlaps are the result of the ratio of the room dimensions 驻波的叠加与否和房间各边的比例密切相关 Intensity of room modes is determined by the wall density and stiffness 驻波共振强度取决于墙壁材料的密度和硬度,32,Standing Wave Pressure Representation for 1st, 2nd, 3rd, 4th Harmonics 房间内1/2/3/4次谐波的声压分布,1st Harmonic,2nd Harmonic,3rd Harmonic,4th Harmonic,1/8,1/6,1/2,1/4,3/4,1/2,5/6,5/8,7/8,3/8,33,Standing Waves Pressure Polarity 驻波的极性,The acoustic polarity changes around the null 声学极性在零点附件发生变化,1st Harmonic 1次谐波,+,_,1/2,34,Standing Waves Pressure Polarities,+,_,+,+,+,+,+,+,+,_,_,_,_,_,1st Harmonic,2nd Harmonic,3rd Harmonic,4th Harmonic,1/8,1/6,1/2,1/4,3/4,1/2,5/6,5/8,7/8,3/8,35,Standing Waves Modal decay 驻波模态衰减,Example of room modal decay plot 房间驻波模态衰减样图 Very uneven response 不平坦频率响应 Long decay of a just a few frequencies 部分频率出现衰减时间过长的现象 An audible effect of room modes 驻波现象是可以听到的,Copyright 2005 PMI, Ltd.,36,Modeling Software CARA 房间声学建模软件CARA,To Control Standing Waves (They Cannot Be Eliminated) 控制低频驻波（驻波无法被完全消除）,Change one or more dimensions - Minimizes over lapping frequencies Aim for even modal distribution (5% difference) 改变房间某一边或者更多边的尺寸，尽可能地减少共振频率叠加的可 能性，目标是更均匀的模态分布（共振频率间隔5%） Move subwoofer location - Drive mode out-of-phase to reduce relative amplitude 改变超低音的位置驱动驻波的原始声学相位发声反转而降低共振频率 Move seating location - Moves the listener out of peaks and dips 改变座位的位置使观众远离驻波的波峰和波谷 Use bass absorption or absorptive walls 使用低频吸声材料或建造吸声墙 Equalize LAST 均衡器最后的救命稻草！,38,Standing Waves 1 驻波第1节 Dimensions Resonance Frequencies 共振频率的计算,Equation: 计算公式 F = n1130/2D (in ft) F = n345/2D (in m) Where F is frequency F是共振频率 n is the harmonic n代表第n次谐波 D is the distance between walls D是房间内两面平行墙之间的距离,39,Solutions to Standing Waves -1驻波解决方案 Room Dimensions 房间尺寸,Determine room dimensions 确定房间的尺寸 Determine modes (F=n1130/2d) 确定共振频率 Find modal overlaps 找出“简并”的共振频率 Locate dips for 1st, 2nd, 3rd, 4th harmonics 找出1-4次谐波的波谷位置,40,Calculation programs 可使用的计算软件 RPG Room Optimizer CARA THX Room Mode Calc Stereophile Guide to Home Theatre PMI modeling program,Solutions to Standing Waves -1驻波解决方案 Room Dimensions 房间尺寸,41,Calculating Standing Waves -1 计算驻波,Copyright 2005 PMI, Ltd.,42,Loudspeaker,Listener,Solutions to Standing Waves 1驻波解决方案 Room Shapes 房间形状,Complicates Acoustic modeling and computations 声学建模和计算变得复杂化 Does not get rid of standing waves or reflections 并未消除驻波和声反射 Not recommended 不推荐！,43,Solutions to Standing Waves 4 解决方案Diaphragmatic Absorption 薄板共振吸音,Diaphragm,Absorber units are resonating surface tuned to problem frequencies 吸音体是特别针对问题频率而设计 Absorber box is filled with “fuzz” 箱体内充满了多孔吸声材料 Works 50Hz to 150Hz 有效工作频段为50-150Hz Design of bass absorber is complex difficult to get consistent results 设计低频吸声体复杂产品的一致性不理想 Place in high pressure zone 将低频吸音体放在低频声压较高的区域将增大吸收效率,44,Solutions to Standing Waves - 4驻波解决方案Helmholtz Absorption 亥霍姆兹共振腔,Helmholtz units are tuned to problem frequency 亥霍姆兹共振腔可专门针对问题频率来设计 Absorber box is filled with fuzz 箱体内充满多孔吸音材料 Works down to 80Hz 最低工作频率为80Hz Design of Helmholtz absorber is extremely complex 设计这种吸音体非常复杂 Amount of absorption depends on open surface area. 吸收量取决于开孔尺寸,45,Solutions to Standing Waves - 4驻波解决方案 Resilient Walls 弹性减力墙,Resilient walls dont reflect bass well 弹性减力墙对低频的反射较弱 Sound energy is absorbed by the PAC RSIC rubber isolator 低频声能被PAC RSIC橡胶隔离器所吸收 Add Soundboard or Loaded Vinyl to spread the resonance frequency 增加吸声板和弹性苏联能拓宽吸收的频率范围 You get isolation too! 同时还起到隔声的作用！,46,Solutions to Standing Waves 4驻波解决方案 Resilient Walls PAC RSIC1弹性减力墙 PAC RSIC,47,Solutions to Standing Waves 4驻波解决方案 Resilient Walls PAC RSIC1弹性减力墙 PAC RSIC,48,The Room 房间,Sound Isolation 隔声,49,Designing The Room The Sound 房间声学设计,Good sound isolation means: use the room anytime! 好的隔声效果意味着：可以随时使用视听室 Very low background noise lose none of the soundtrack subtlety 非常低的背景噪音可以听到声轨中的每一个细节 Privacy 隐私,Airborne Transmission Path 空气传声 Isolate doors, windows, and plumbing 隔离门、窗户和下水管道 Isolate, seal and caulk all leakage paths 隔离、密封所有漏音的通道 Structure Borne Transmission Path 结构传声 Special wall structures 特殊的墙体结构 Floating floor 浮筑地板 Floating ceiling 悬浮天花,Sound Isolation 2 Flanking Paths 隔声,51,Noise Transmission Detection 噪音传输检测,Pink Noise Bursts 粉红噪音发生器,Listen! Detect! Fix It! 聆听并 解决问题,Caulk 涂料粉刷,Expand Foam 泡沫喷涂,AC Outlet 电插座,Weather Strip 橡胶条,52,Offset Flanking Paths 错开声传输途径,In-Line Doors Allow a Direct Path for Noise,Offset Doors Reduce Sound Transmission,Sound Path,Sound Path,Office,Hallway,Theater,Bedroom,Worse 糟糕,Better 良好,Hallway,53,Isolation Solutions 隔声,Wall Construction 墙体结构,Isolation Strategies 隔声的策略,More Mass 厚重的材料 Damp resonance 降低共振 Decouple 断开声桥 Larger air gap 增大通气口,55,Wall Construction Decoupling 墙体结构断开声桥,56,Isolating the Ceiling and Floor 隔离天花和地板,*Room must also be isolated from building structure for max isolation. 房间本体也必须采用特殊建筑结构以达到最大隔声效果 Floating floor construction浮筑地板结构,Existing concrete floor,Carpet + Duracoustic mat 地毯+双层隔声垫,3/4“ T&G Plywood 胶合板,Isolation Pads 隔离垫,5/8” sheetrock,Vinyl barrier or ½” soundboard 隔声板,RSIC or Isomax 隔离器,Hat Channel 隔声通道,Joist龙骨,Floating ceiling construction (PAC RSCI-1 Isolators) 悬浮天花结构,Or use single layer Quietrock 或者使用单层Quietrock,57,Isolation Doors and Windows 隔声门和窗户,Eliminate Windows尽量避免使用窗户 Use high isolation windows使用隔声量高的窗 Eliminate unnecessary doors 避免不必要的门 Two doors as sound lock双门结构形成声闸 Acoustic isolation doors 使用隔音门 Use exterior doors 房间外面再加一道门 Correctly installed with abundant caulk 正确使用大量的填缝胶 Maintain seals 定期对密封处进行维护,THX Confidential 58,Acoustic Testing Facillities 声学测试机构,Orfield Labs Minneapolis Harley Davidson Riverbank Acoustical Labs Geneva, Ill NRC Canada Ottawa, Canada NASA Acoustical Testing Lab Cleveland, OH Western Electro-Acoustical Testing Labs - Santa Clarita, CA,59,The Room 房间,Background Noise 背景噪声,Background Noise 背景噪声,Interferes with loudness perception 与人类的主观响度感受相关 Masks low level signals and detail 掩盖了节目中的低电平细节信号 Transient noise is distracting 瞬态噪音将分散观众的注意力,Sources of Background Noise 背景噪声源,Local sources 本地噪声源 HVAC 空调暖通系统 Plumbing排水系统 Fans 风扇 Pumps/Compressors 水泵/空气压缩机 Washer/Dryers 洗衣机/干衣机 Garage door openers 车库卷帘门 Projectors投影机,62,Sources of Background Noise 背景噪声源,External sources 外部噪声 Traffic 交通 Airplanes 飞机 Wind 风 Neighbors 邻居,THX Confidential 63,NC Curves,Measuring Background Noise 测试背景噪声,Use spectrum analyzer 使用频谱分析仪 Use a low noise microphone 使用低噪音测试麦克风 Take a time and space average 使用时间和空间平均值算法 Use NC weighting 使用NC计权 Plug your ears, wait, unplug and listen 塞住耳朵几秒钟后放开，进行聆听 Use Earplugs, or fingers 使用耳塞而不是手指,Solutions to Background Noise 背景噪声的解决方案,Large air ducts for lower air velocity 大口径通风管道能降低空气的流速 Longer ducts with several turns 弯角较多的加长通风管道 Plenum silencers 空调消声器 Lined ductwork 管道内壁设有纹路 “Whistle Free” air grilles 没有“吹哨声”的通风口 Isolate motors on suspension or move 将马达移走或者使用弹性减振装置 Completely seal windows, doors, etc. 将门和窗都堵严实,66,The Room 房间,Vibration Control and Rattles 控制振动和共振,67,Rattles 共振现象,Very prominent for low frequency signals 播放低频的时候特别明显 These are usually caused by acoustical or mechanical coupling with loose fixtures, lights, furniture, and doors. 这种现象通常是由声学或者物理接触引起的，松动的灯具、家具和门可能会产生共振 Rattles can sound like speaker or amplifier distortion, and their localization can be distracting. 共振听起来象扬声器或者放大器失真，共振源会引起观众的注意，分散他们的注意力,68,Rattle Detection 检测共振,Single Tone Oscillator Sweep slowly from 20 Hz to 1 kHz 信号发生器播放20Hz-1KHz 的扫频信号,Rattle !,Listen! Look! Fix It!,Caulk,Felt,69,Rattles (continued) 共振,Method: use slow varying frequency sweep 使用不同的频率扫描信号 Check 检查 Furniture家具 Glass Surfaces 玻璃表面 Track Lights 轨道灯 Hung Pictures 悬挂的画,Walls and Doors墙和门 Fixtures 家具 HVAC Ducts and Vents 空调暖通系统和通风口 Ventilation System 换气系统,Solutions to Rattles 共振的解决方案,De-couple loudspeakers from room surfaces 将扬声器与房间本体隔离 Add elastic mass to surfaces 在共振体表面增加弹性物体 Tighten loose fixtures 上紧灯具 Isolate fixtures with 使用以下手段隔离灯具 Rubber Pads 橡胶垫 Caulk 填缝胶 Insulation 海绵/玻璃棉等,71