Low-frequency instruments (kick, bass guitar, string bass, etc.) exhibit two different aspects of perceived "loudness". One is volume, and the other is bass response.
You can make these instruments appear louder by either raising the fader level (volume), OR by increasing the low end response by making eq adjustments (bass response). If you boost the low end, the bass (or kick) will now appear louder, but ONLY on large speakers. If you mix only on one set of speakers, and these speakers have a good degree of low end, then you will be somewhat in the dark as to how this will "translate" to other (smaller) speaker systems.
The solution is to have a small set of speakers to switch to periodically while mixing. Speakers so small that they do not have "warmth", speakers that are devoid of "boom". In other words, speakers that do not have any real degree of "low end". Can you still hear the kick? Can you make out the bass? If not, you either need to raise the level of these instruments, or raise some of the mids and highs of these instruments. Then switch back to the larger speakers? Bass and/or kick now too loud? Then roll off some of the low end. Go back and forth until the kick and bass are the same apparent level on both sets of speakers.
-Mark Dann
Mark Dann Recording
July 07