voice pipe

... 传热性,传热度 thermal conductivity 传声管 voice pipe (or tube) 传声器,麦克风 speaking trumpet (or megaphone) ...

 voice channel

... voice carrier 音频载波 voice channel 传声管 voice communication 音频通信 ...

 voice tube

传声管(voice tube), 此释义来源于网络辞典。