A test and measurement instrument for generating an analog waveform, including an interpolator configured to receive a digital signal and output interpolated samples of the digital signal at a sample rate, a filter modulation controller configured to output first filter coefficients at a first time and second filter coefficients at a second time, a convolver configured to generate a convolved signal by convolving the interpolated samples of the digital signal and the first filter coefficients and convolving the interpolated samples of the digital signal and the second filter coefficients; and a digital-to-analog converter configured to convert the convolved signal to an analog signal based on a fixed, constant clock signal.