To paraphrase Claerbout 1992b, one way to synthesize new seismic traces is to ensure that, after specified filtering, they have minimum power. Filtering is spectral multiplication, so the specified filtering is a way of prescribing a spectrum for the new traces. You are free to choose a spectrum to prescribe. A sensible choice is the spectrum of the recorded data, which can be captured, in a sense, by finding the data's PEF.