So I bought a pair of these wonders earlier this year and when I heard the final result (in their case), I was totally amazed to emit low as the 12 inch! I already made two evenings, it runs with a C2 in JBSystems and an active filter Behringer cut at 120 Hz and it is a real treat! At first I was skeptical about a 12 inch sub but I wanted compact boxes and so I built mth 30 and the ratio of weight to height - power and also the price is exceptional!! We recover the RCF quality! Ideal for DIY design for subs superior quality at lower costs. I recommend it 200% and I do it again this choice without hesitation.