Unferth:
Finally, I get to hear from a Tumult owner. Congratulations on your choice of Adire Audio. I happen to be a fan of their drivers. I have a Shiva subwoofer built from ground up. It weighs about 150 lbs and I put 2 casters towards the rear which saves my back when relocating it (just lift the front and push or pull).

I’m surprised that yours clipped with 500 watt amp. How loud were you running it? My Shiva never clipped even when turned up to door shaking volume and its efficiency is at 87 db. I use 150 watt amp from Parts Express and the enclosure is 5 cu ft with 15 inch passive radiator.

Those of you with expertise on speaker design, does Vas number matter a lot for subwoofer drivers? Adire’s Tempest which is also a 15 inch driver, has half as much of Xmax distance but almost twice as much of Vas as Tumult does. What does this mean in terms of the potential of each driver?