View Full Version : Specific Port v. Sealed question

12-29-2006, 11:49 PM
I am getting an IDMax 12" and trying to decide on the type of enclosure to use. I am trying to build good system. By good I don't mean loud, I mean good sound reproduction. I don't need to be heard from a mile away, I just want good sounding loud music inside. I figure 1000w on a sub will be loud enough for me no matter what type of enclosure, so would like the best SQ the sub can do. I have tried to do a lot of reading of old threads and searching for info, and have, if my thinking is correct, come to the conclusion to go with a sealed 1.3cu ft box.

Am I thinking correctly for a daily driver setup that will play a wide variety of music?

12-30-2006, 02:47 AM
For the flattest response curve (assuming cabin gain doesn't provide massive dB gains) the box needs to be aligned at a Qtc value of 0.707.

An easier way to explain this is that the net volume of the sealed box needs to be:

Vb = Vas / [(0.499849)/(Qts^2) - 1]


Vb = net volume of sealed enclosure
Vas and Qts are T/S parameters for your driver. You can probably find these variables in your owner's manual or by contacting the manufacturer.