A magnetic-tape apparatus comprises a device for the power-assisted actuation of a tape-sensing lever during switching from the playing mode of the apparatus to the reverse-search mode of the apparatus. The direction of rotation of the reel discs is changed by means of a pivotal drive mechanism which is driven by a drive motor. The power for the controlled actuation of the tape-sensing lever is obtained in that a coupling gear associated with the pivotal drive mechanism engages with a stationary gear pin. This ensures that the coupling gear performs a controlled movement, which is used for controlling the tape-sensing lever.