Contact transducer for musical instruments with soundboard, comprising: vibrating element, consisting of an air core coil made of enameled copper wire, suitable to be placed in contact with the soundboard of any musical instrument, and able to vibrate according to said soundboard; magnetic field generator, consisting of a permanent magnet, preferably made of neodymium, suitable to transform the vibrations of the vibrating element induced by the soundboard in electric signals, according to the principle of electromagnetic induction; sound-insulating separator made of elastic material, on which the magnetic field generator is fixed, keeping it firmly and close to the vibrating element, and isolating it from the vibrations of the soundboard; electric cable connected to the ends of the copper wire of the vibrating element with at least one connector suitable to transfer the electrical signal generated to at least one sound amplification device.