A universal device is for preparation of a watch with a gain/loss correction crown and an oscillating resonator. The device includes winding and a gain/loss corrector with a robotic manipulator for manoeuvring the crown. It also includes an adjustment device with a gain/loss correction device including a gain/loss-corrector oscillator generating an oscillation to subject the watch to an oscillation at a correction frequency NC and/or to a modulated movement. The gain/loss correction device includes a gain/loss controller that controls the oscillation of the gain/loss-corrector oscillator, interfaced with a device to measure the gain/loss of the watch. The gain/loss correction device also includes an automatic winder with a watch-holder stand subjected to the oscillations or movements generated by the gain/loss-corrector oscillator.