Provides mechanical oscillations when given input signals from an oscillator or AF oscillator. A specially designed coil system enables the unit to be operated at its maximum rang for a prolonged period without any damage due to overheating. The frequency response encompasses the whole of the audio spectrum and beyond. Electrical input via a pair of 4mm shielded sockets and oscillating mechanical output is available through a shaft at the top. A locking arrangement provides safety to the apparatus during storage or transportation by blocking the moon of the shaft.