Controllable piezoelectric layers can be used for cancelling echoes from reflecting surfaces. A regulator circuit for controlling a two-layer system with thin PVDF layers has been designed and manufactured. Tank measurements have been carried out to verify the regulator design and the echo reducing ability of the double layer. If the layer, which is used as a transmitter is controlled with an amplitude, matched replica of the signal that is sent towards the double layer system, cancelling of the echo is achieved. A corresponding echo cancelling performance has not yet been measured for the complete system with the regulator included.