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RP22沉浸式音频设计推荐规范，音频性能目标

RP22推荐规范对高品质的音频系统能够达到的性能目标一共有8个方面，包括Dialog clarity对白清晰度、Localization accuracy声音定位精度、Sound movement声音移动、Sound field immersion and envelopment声场沉浸感与包围感、Tonal balance (timbre)色调平衡(音色)、Dynamic range动态范围、Bass impact低音效果、Audience coverage听众覆盖、Sound isolation隔声。当中每一点与沉浸式音效系统设计相关的要点具体如下。

与Dialog clarity对白清晰度相关的系统设计要点：

●Speaker frequency response扬声器频率响应

●Speaker directivity index扬声器指向性指标

●Speaker sound power扬声器声功率

●Speaker audience coverage扬声器的声音覆盖范围

●Speaker mounting and placement扬声器安装与摆放

●Room acoustics including direct to reflected sound ratio (D/R), reflection decay time, flutter echoes, and standing wave resonances室内声学，包括直达声与反射声比值(D/R)、反射声衰减时间、颤动回声和驻波共振

●Background noise levels and spectrum背景噪声等级和频谱

与Localization accuracy声音定位精度相关的系统设计要点：

●Number of discrete speaker feeds and corresponding speaker positioning独立渲染的扬声器数量和相应的扬声器定位

●Audio format decoding and rendering capability音频格式解码和渲染能力

●Interchannel level calibration通道间电平校准

●Interchannel time synchronization calibration通道间时间同步校准

●Interchannel phase and accuracy of frequency range通道间相位和频率范围精度

●Speaker directivity index扬声器指向性指标

●Speaker audience coverage扬声器声音覆盖范围

●Room acoustics, including reflection decay time and flutter echoes室内声学，包括反射衰减时间和颤动回声

与Sound movement声音移动相关的系统设计要点：

●Number of discrete speaker feeds and corresponding speaker positioning独立渲染的扬声器数量和相应的扬声器定位

●Audio format decoding and rendering capability音频格式解码和渲染能力

●Interchannel level calibration通道间电平校准

●Interchannel time synchronization calibration通道间时间同步校准

●Interchannel timbre, frequency and phase accuracy通道间音色、频率与相位精度

●Speaker audience coverage扬声器声音覆盖范围

●Room acoustics, including reflection decay time and flutter echoes室内声学，包括反射衰减时间和颤动回声

与Sound field immersion and envelopment声场沉浸感与包围感相关的系统设计要点：

●Number of discrete speaker feeds and corresponding speaker positioning独立渲染的扬声器数量和相应的扬声器定位

●Interchannel level calibration通道间电平校准

●Interchannel time synchronization calibration通道间时间同步校准

●Interchannel timbre, frequency, and phase accuracy通道间音色、频率与相位精度

●Speaker audience coverage扬声器声音覆盖范围

●Room acoustics, including reflection decay time and flutter echoes室内声学，包括反射衰减时间和颤动回声

与Tonal balance (TIMBRE)色调平衡(音色)相关的系统设计要点：

●Speaker on-axis and off-axis frequency response扬声器同轴和离轴频率响应

●Speaker sound power response扬声器声功率响应

●Speaker audience coverage扬声器声音覆盖范围

●Speaker placement扬声器摆位

●Reflection decay spectral balance反射声衰减频谱平衡

●Standing wave resonances驻波共振

●Digital signal processing (DSP) settings during calibration校准期间的数字信号处理(DSP)设置

●Quality and settings of spectrum analysis equipment频谱分析设备的质量和设置

与Dynamic range动态范围相关的系统设计要点：

●Speaker and subwoofer output sound pressure level扬声器和低音炮输出声压级

●Background noise in the room, due to ventilation, street noise, machinery, projector and equipment fans, etc., which can mask low level details and erode dynamic range房间内的背景噪音，包括通风、街道噪音、机械、投影机和其他设备风扇等，可能会掩盖低级细节并削弱动态范围

●Electronic noise or hiss in the equipment设备中的电子噪音或嘶嘶声

●Poor sound isolation from adjacent noisy rooms较差的隔声处理，邻近嘈杂房间带来的影响

●Excessive reflection decay time that smears dynamics and raises the perceived background

noise level 过高的反射声延迟时间会影响动态，并提升可感知的背景噪声等级

●Amplifier output power功放输出功率

与Bass impact低音效果相关的系统设计要点：

●Subwoofer amplifier output power低音炮功放输出功率

●Subwoofer(s) output sound pressure level (SPL)低音炮输出声压级（SPL）

●Bass headroom of all speakers所有扬声器的低音动态余量

●Subwoofer and speaker placement低音炮与扬声器的摆位

●Standing waves / room modes驻波/房间模式

●Acoustical control of bass energy (wall damping, bass traps, etc.) 低音能量的声学控制(墙壁阻尼、低频陷阱等)

●Bass optimization, including calibration低音优化，包括校准

与Audience coverage听众覆盖相关的系统设计要点：

●Speaker sound power response扬声器声功率响应

●Speaker dispersion扬声器的声音扩散特性

●Speaker count and placement扬声器的数量与摆位

●Subwoofer number and placement低音炮的数量与摆位

●Standing wave resonances / room modes驻波共振/房间模式

●Calibration of frequency response, time synchronization, and levels频率响应、时间同步和电平校准

●Room acoustics, including reflection decay time and flutter echoes室内声学，包括反射衰减时间和颤动回声

与Sound isolation隔声相关的系统设计要点：

●Wall, floor, ceiling, and door construction墙壁、地板、天花板、门结构

●Ventilation systems with common paths to other rooms通风系统与其他房间有公共路径

●Plumbing and other mechanical equipment that can conduct sounds and vibration管道和其他能传导声音和振动的机械设备

●Small flanking paths that leak sound, such as electrical boxes and conduit pass-throughs. 容易泄漏声音的侧面小路径，例如配电箱和导管通道