Q: I see a lot of subs marketing below 20Hz but there is very little musical or movie information there correct? Your subs roll off at 27Hz or so. Is that due to driver selection or DSP limitation ? What dB are your VS21 or DJ118 outputting below 20Hz?
Is Dubstep EDM etc mostly 30Hz and above ?
Musical genres aren't limited to frequency ranges. Producers make those choices. The vast majority of all music, including those genres, rarely include low frequencies. The lower the frequency, the less often it is present. The lower the note, the more scarce it is. There's more 60 than 50, more 50 than 40, more 40 than 30, more 30 than 20 and there's so little 20 that going to 10 results in almost none. For now. Some genres include deeper notes more often than others. Extremely fast-paced beats such as in psy-trance, don't allow for low-frequency content in the drums although it uses the drums for the energy and impact. Thus the lowest frequencies common in psi-trace are about 55 to 60Hz. Equally fast-paced drum-n-bass uses sustained low tones and creates the rhythms at higher frequencies. Those tones can extend into the low 40s, but not very often into the low 30s. 30s are rare and I find them in glitch-hop and hip-hop/rap. 20s are so rare that I can't even find a pattern.
There isn't much content in recorded music or movies below wherever the producer chose to filter it. It used to be filtered at higher frequencies than it is now. The reasons for the filtering are technological/equipment limitations. If you can't record it or reproduce it, you don't even know it's missing. If you can record it but not reproduce it, you filter it out so as not to put the reproduction mechanisms under excess stress.
The other side of the equation is, we can't buy mass-produced transducers that operate efficiently in very low frequencies because the lack of demand precludes them being mass-produced. It takes a massive vision and a vast investment to break new ground, or go into the unexplored. You need motivation, commitment and capital.