Compact models are typically used for leak detection survey work using contact mics, but also include accessories for ground work.
The Stethophon 04 from Sewerin is designed to be a fully-featured compact leak detector featuring a built-in contact microphone providing undistorted sound reproduction, even when the noise is barely audible. The Stethophon 04 can be equipped with either wired headphones or with Sewerin SDR wireless headphones. When using the Sewer SDR headphones, the unit will automatically connect to headphones when unit and the wireless headphones are switched on. Sewerin SDR wireless digital signal processing technology prevents acoustical interference, e.g., hissing, re-amplifying, etc. Every Stethophon 04 feature user selectable audible filter functions, enabling users to listen to the sound frequency of the leak noise while filtering nuisance noises.