Adobe audition -> open waveform -> spectral view (F9) -> zoom in on kick's freqs (roll your mouse wheel on the ruler to the right to zoom in, then drag up and down, likewise for the ruler at the top which represents the time axis) -> work out which of the coloured blobs represents your kick...it'll probably be down near the bottom of course -> use marquee tool to put a selection box around kick's freqs -> effects tab, amplitude, amplify/fade -> -30 db.

You may have to select a few areas with the marquee tool and fade each of them, because kicks are generally shaped like an L or a backwards J.