ClearOne会议系统产品基础-房间设计原理培训课件.ppt

房间音频设计原理 议程 Scoping机会 了解用户需求 确定声音环境 音箱 麦克 Scoping 收集所需要的信息来创建合适的系统设计并获得所需要的信息来建议房间环境 房间的特征是什么？ 是闹还是静 是固定的还是可重新配置的 环境噪音电平 反射和回响 确定用户需求 他们对房间的期望是什么 对于会议空间有没有计划 多少与会者 预算 房间声学 可理解性 在理解会谈方面有没有困难 由下列因素影响： 房间的活跃度（反射） 回响 环境噪音 反射和回响 反射 当声能跳离封闭空间的表面而产生反射。多个反射能引起声音听起来很空或很乱。 回响 回响是由来自多个反射的声能堆积而成的。它始终贯穿整个封闭空间。回响减低了声音的可理解范围。 可以通过声音处理控制 环境噪音 影响 发送和接收的理解性 回声控制 互相作用 高的环境噪音能够被传给会议中的听众并引起疲劳感 噪音 如果信噪比是: 0 - 10 dB - 可理解性是不可接受的 10 - 20 dB - 可理解性不太好 20 - 30 dB - 可理解性好 30 dB + - 可理解性最好 噪音常见源 Air handling systems (especially with ceiling mounted microphones) Fluorescent lighting Equipment noise Projectors Computers External sources Increasing Speech to Noise Ratio Get the talker closer to the microphone Remove the source of the noise Room treatment / isolation materials Electronic noise cancellation Solutions Room Treatment Acoustic panels Curtains on windows Carpeting Sound Isolation Enclosures for equipment with fans Electrical / Mechanical noise reduction Move ductwork (if possible) Microphone Types Pickup Patterns A clear, strong pickup of the talker’s voice is an essential step for good audioconferencing Table mics Gooseneck mics Ceiling mics Lapel mics Handheld mics Microphone Pickup Patterns Unidirectional Omnidirectonal Speaker and Microphone Placement Guidelines for Mic Speaker Placement Get microphones as close to the talker as is practical Use one mic for every two participants Use multiple speakers to cover listening area Distributed speaker systems with proper room layout Maximize the distance between speakers and microphones Microphone Placement Position microphone close to talker Increases clarity Limit number of open microphones Reduces transmitted noise Consider microphone pick up pattern Directional microphones pick up less background noise Use ceiling microphones cautiously Increases background noise and decreases intelligibility Critical Distance The distance from the sound source where the sound l