the present invention is directed to compensating the sin / x response attendant the output signals from a digital - to - analog converter in systems consisting of the cascade connection of a digital processor having a non - uniform frequency response h and a digital - to - analog converter . this is accomplished by altering the processor to provide a frequency response of h * g , where h is the impulse response of the processor , g is the impulse response of the reciprocal of the frequency response of the dac , and the asterisk represents convolution . alternatively , if the fourier transform of the frequency response of the processor is given by f , and the dac exhibits a frequency response s , which is the frequency transform of the time response of the dac sample and hold type output , then the processor is substituted with one having a frequency response defined by the inverse fourier transform if / s )) over the frequency band of interest .