Help with DIY Subwoofer planning

[smsibana]

Greetings everyone, im new here!

I wanted to build a sealed passive subwoofer for my 18,5m^2 room, mostly for music, some movie capability would be nice but not the focus. 70/30 Music/movie id say. Powering the sub will be a Behringer nx3000, and for DSP im currently using my pc. Also have a UMIK-1 on the way.

I personally really like the way that the Dayton Ultimax umii12 22 12inch driver looks, and it should be capable enough to be used for both music and movies. It might not be the best fit for my needs, but I'm thinking that it will do well enough, right?

Now the problem is the box design, with the factory parameters, getting a qtc of 0,7 would require something around 90-100L net volume, which is quite something for a sealed 12 inch. 
There was however an audioexpress article that measured the parameters of this specific driver, and found some pretty interesting values. Using the measured parameters, the sub reaches a qtc of 0.54 in a 50L enclosure.
This however complicated WinISD simulations. Using the averaged measured parameters, the other parameters that WinISD calculates are very different from the factory specs, for example: Mms of 428 instead of 189, BL of 23,6 instead of 14,8 and Cms of 0,066 instead of 0,133. 
At this point I'm not really sure what parameters to use for simulation purposes, and what size box to choose..

Does anyone have some opinions on this, or possibly experience with this specific driver?
Any help is appreciated, many thanks!












https://audioxpress.com/article/test-ben...oofer-line

[walwal]

If the Sub is active, you dont need the TSP, put it in 40-60 L sealed and measure at the listening position, then equalise it with your DSP.

[smsibana]

If the Sub is active, you dont need the TSP, put it in 40-60 L sealed and measure at the listening position, then equalise it with your DSP.

Do you mean that, because i will be using dsp, the size of the box isn't too important, as long as its not way too small or too large? Or in what way are the TSP not important anymore. Thanks for the answer by the way!

[walwal]

Both. The size ist not that important, also the TSP. TSP are important für passive speakers. The size ist much important for Ported subs.

But the room has a real big influence for frequency response.

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