摘要 |
A protective breathing mask, in addition to having a speaking diaphragm for close communication is equipped with an electroacoustic transducer system for indirect speech transmission from inside the mask. In order to achieve high transmission quality for human speech with a simple apparatus without the occurrence of interference noise, it is provided that the sound output channel is closed on the mask side by an auxiliary diaphragm which is acoustically coupled with the speaking diaphragm via a secondary air chamber, and is also mechanically connected directly or indirectly with a movable element of the electroacoustic transducer system. |