The technique of mixing kick and bass is often a common struggle that beginners are prone to deal with on a constant basis. This is mainly because noobs fail to understand that for particular genres of music the listener is not used to hearing so much bass in the song. Instead, they do the opposite.

Of course, there are certain cases where listeners want to hear rumbling bass notes otherwise they would consider the song to be extremely "weak" especially for the following genres of music:
  • Reggae
  • Dub Reggae
  • Rap/Hip Hop
  • Dubstep
  • Drum and Bass
  • etc.

How Loud Should The Bass Be?​

The loudness of your bass should always be mainly determined by either the genre of music or a client/artist/producer's preference. But a good guideline is to have your kick peaking at -6 dBFS and your bass at -12 before the audio mastering stage.

Note: always remember to trust your ears rather than following dBFS metering numbers strictly. Although general audio mixing guidelines may be useful as a starting point.

Furthermore, to appropriately determine your bass and kick drum's volume I'd recommended you to follow these steps:

Use references tracks of songs you like.
Conduct a feasibility study with a brickwall limiter to check where things are.
If everything is fine and sounds nice, of course, you are on the right track (no pun intended).

In summary, you generally want your kick drum, bass synth, bass guitar, or 808s to have a good balance such that the human mastering engineer or AI instant mastering service can push the song to about -7 dB or -8 dB LUFS/LKFS level without being bothered by the low-end.
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