5. When all else fails, try adding a little EQ. A parametric (or console EQ with sweepable mids) works well for this application, but a graphic can work fine. Boost the gain on the EQ, listen to the kick, and slowly sweep the EQ frequency until you find the frequency you want to bring out. Next, adjust the EQ gain to your taste. In addition to boosting some frequencies, you might want to experiment with cutting some of the boomier frequencies out to clear the top end a bit.