The influence of ultrasound on benzaldehyde and benzoquinone electroreduction in various solvents has been investigated with a new type of sonoelectroreactor characterized by the working electrode acting also as the sonotrode. Both cyclic voltammetry and electrolysis at constant applied potential suggest that the electrode-solution interface and the mass transport rate are considerably affected by ultrasonic irradiation. Rates of production of reduced organic compounds are generally enhanced via an increase of current intensity but no switch of reaction mechanism due to ultrasound is observed.