| speaking tube | (n) a tube for conveying the sound of a voice from one room to another |
| 伝音器 | [でんおんき, den'onki] (n) megaphone; speaking tube; sound box [Add to Longdo] |
| 伝声管 | [でんせいかん, denseikan] (n) speaking tube; voice pipe [Add to Longdo] |
| 伝声器 | [でんせいき, denseiki] (n) speaking tube [Add to Longdo] |