Not as earth shaking as my Dayton UM18-22 in 4 cuft sealed (driven by external plate amp from Elemental Design A7-450). But that is an 18" and a larger cabinet. Very 'tight' bass. Still need to do more listening, exploring (and get cable situation/connectors resolved; trying to maintain the existing large/small femal space, but don't have matching male ones; and need to make proper (big, now that I have seen 800-1000w peak (based on 'clipping' light on amp) going into the sub, that is quite some ampere flowing!). I expect the DEEP section to further improve with the Velodyne control software/hardware once the amp is back.