Abstract: An acoustical key generated from a finite random data source of a random acoustical signature, wherein a key generator generates the acoustical key. The key generator creates a bit field array of bit values from a data file and derives a plurality of intersection points of the array with the finite random data source to form the key with the bit values. In one embodiment, the data file is unaltered and the key can be used to authenticate the data file if used for data integrity. In another embodiment, at least one Tau offset may be used to establish a first bit value for said filling of the two dimensional array. In addition, at least one Phi offset may be used to establish a first key value for the key.