You are in Europe correct? If so I don’t think Stereo Integrity ships internationally but I could be wrong.
can tell us that.
Regarding the differences between boxes I will graph it for you later if I have time but an educated guess would be that a single 21” in a ported box would be the same or better than a single 24” in a sealed box until a couple hz below the tuning frequency of the ported box, which I think for you is around 17hz, so I’m your case maybe like 15hz the sealed box starts to do better.
This of course is WITHOUT factoring in room gain, which is unique to each room.
Also a sealed driver needs a lot more power than a ported box, especially down low, so your going to need a pricier amp like speakerpower to get the most out of a sealed sub as many amps are not great at providing their amp power below 15hz.
All that said, this doesn’t mean each option won’t be more than your need. At some point the graphs just become numbers as you may not be someone who wants to crank your sub to 130db, maybe 100 is fine for you, and maybe both subs can do that as well.
So don’t get too hung up on the numbers (like I do lol).
can tell us the box size of the 10 cubic kit box I think
Sent from my iPhone using Tapatalk (so ignore any typos grammatical errors because my iPhone predictive text stinks)