if u want a harder sounding kick just up tha 250hz freq by about 1.6 - 2dbl and give it a little reverb... if u feel to make some decent sounding kick i suggest u use the legacy effects that come in the samplers on fl studio. i do not know y the legacy effect do not show by default but to enable it just click options, then general settings and click the show legacy effects tab now at the bottom of the samplers u should c some new options show up, u hear more drastic results with percussions.