The sound-reproducing device according to the first embodiment of the invention comprises a front and back covers fastened together with sheets located therebetween, a sound message reproducing unit, a impact sensors unit and sheet position detecting unit the output of which is connected to an additional input of sound message reproducing unit. This provides an automatic detection of the number of the open sheet taken into account when a sound message is selected. Impact sensors unit comprises an activation point detection unit, N sensors, a commutator, and a pulse former. The activation point is determined according to capacity changes between the cirresponding sensor and the common bus. The sound-reproducing device according to the second embodiment of the invention further comprises a message number forming unit, the first and second inputs of which are connected to the outputs of sheet position detection unit and impact sensors unit, and the output is connected to the input of sound message reproducing unit. Both embodiments provide a reliable operation of the device with a big number of book sheets.