It's not uncommon for such comments, particularly with EDM and electronica genres.
Horn subs naturally filter the harmonics which you get when using direct radiator subs, which is what makes it appear to lack mid bass (in comparison).
This generally leads to horn subs being described as "smooth" and "clean" (in comparison to direct radiators).
Are you room tuning your EQ every time you set up?
Every room is different, so if no, then you need to. Auto EQing should sort out room response and help with the perceived deficits.
When it comes to mid bass, you could bump EQ at the relevant frequencies, but doing so is somewhat global, and as such, make, say, vocals, a problem.
If the bass or kick drum fundamental frequency is say 60Hz, then you would need to bump 120Hz (first harmonic) and maybe 240Hz (second harmonic). Oddly enough, I routinely set 250Hz to around -2dB.
It's a "mud" frequency (along with 400Hz).
Speaking of kick drum, find the fundamental frequency, and get it above 110dB for sternum bruising chest thump. You might like to tweak somewhere between 3-4K for greater bass drum definition too.
Lots of people seem to want to use mid bass reinforcement in EDM. They do so by using what is generically called "kick bins". It adds complexity to the setup, more gear to build, buy and haul, more pack space. You can't use kicks bins in the same band pass as your subs or tops/mains, as that introduces phase response issues between all those cabs.
I'd play around with EQ.
Also consider increasing the overall gain of the subs. But be aware, if you do this, you move the acoustical crossover point of your system.
Tell us everything you are currently doing. Crossover points, what your EQ settings are, signal chain etc etc, and lets see if something pops up...
2 x DR 250 (melded array) with March 2012 plans.
4 x 20" BP102 T39's, 2 x 28" 3012lf loaded underway.
3 x WH8 with melded array.Bunter's Audio and Lighting
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