Axiom Home Page Forums General Discussion Advice from Axiom Owners Anyone heard a SVS PBUltra or PCUltra VS Axioms

The unit I have has a hole in one end.

snicker. snicker.

And my wife wonders why I've started to giggle at my 12-year-old's jokes.

CHICKEN BUTT!

No comment as to size?

The concensus in the DIY community, if there is one, is that large ported is the best. The problem with sealed is that you need EQ and a LOT of power to get a sealed sub to extend really low. That usually introduces distortion.

For example, the MaelstormX 18" driver, because of its high linearity, is very well suited either to a 22-24cu.ft. ported enclosure tuned to 12 Hz, or a sealed enclosure.

Ported, it will have a -3db point of around 12Hz (lower in room), and will hit 113 db at 12Hz with 500w of power applied.

Sealed it will have a -3db point of 30Hz. at 20Hz it will be -8db and at 12 Hz -16db. In order to flatten the curve, you will need to apply EQ, which very quickly introduces distortion. Also, as the driver needs to move more to displace more air for lower frequencies, it needs more power to overcome the natural damping of the sealed enclosure.

The long and short of it being, you get more out of a good driver in a ported enclosure.

24 Cubic Feet?!?! Seriously?

That is very interesting, Fred. Do you believe it is *possible* to get decent output below 30Hz with a sealed box?

Yeah, it will do well in a very large box.

I can't say from first hand experience, but there are a few people that have used highly linear 18" drivers in sealed enclosures that get very good output into the teens. It just takes a lot of power and a very linear driver.

I would always go for a ported sub. If this economy ever recovers I will dedicate some OT$ to a 12ft. cu. ported sub.

18" was a little unbelievable, so I leave it up to your imagination.



(I did that on purpose.)

Oh boy! Dream fodder!