a reverberation - imparting device includes a delay line for storing a signal to which a reverberation effect is to be imparted . the delay line has at least one reading location determining timing for reading out the signal stored therein . an address generator generates basic reading address values for determining the at least one reading location . the basic reading address values are modulated by at least two different random numbers generated by a random number generator to determine reading address values . at least two signals read from the delay line are cross - faded , based on the modulated reading address values , such that the at least two signals are alternately intensified and attenuated with a predetermined phase difference . in a preferred application of the invention , the cross - faded at least two signals are output and delivered to a suitable reverberation - imparting device .