"Active Woofer" for Music

[inrank]

hi,

i have posted quite a lot, with many idea's, but here is quite a real one for me.

Here are the needs/wants -

i would like to make a subwoofer (or Active Woofer really )for for my smallish room (11ft x 11ft with a large bay window).

it will be for strictly music, and to go with some open baffle speakers, so tightness and quality over depth

i would like it to be relatively small, no bigger than 30L really.

it will be placed about 60-70cm off the walls in the bay window.

Here is the design -

A Volt B2500.1 in a 17.5L ported box tuned to 39Hz.

An externally hosted image should be here but it was not working when we last tested it.

Volt B2500.1
http://www.studitech.ru/resque/manuals/volt/Volt_B2500_1.pdf
Dayton 170W Plate Amp
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=300-804


is there anything major wrong with this design?

Below the Gain plot

 

[inrank]

the Time Delay plot

 

[MaVo]

Have a lok at this one:

http://www.linkwitzlab.com/thor-intro.htm

Also take the room influence into account. (room gain and room modes)