Abstract: The invention relates to a device for acoustically controlling the setting and hardening characteristics of a material such as cement. This device comprises a cell body defining a cylindrical body, or measuring chamber, which contains a receptacle adapted to receive the material to be tested. The measuring chamber is extended by its two ends by two cylindrical passages coaxial to said chamber, which comprise each a threaded portion and are associated to sealing means; said cell body further includes two electro-acoustic transducers which are arranged at mutually opposed locations and are facing each other. The novel device is adapted to be used for determining and controlling the setting, hardening and mechanical strength characteristics of cement or similar material under conditions of high pressure and elevated temperatures.