I see some people asking for a subwoofer for their living room where they don't have a lot of space. The Martycube is just too big yet they want better performance in 20 to 50hz range. I asked Ltd02 about using a 15" driver in a 21" cube.
With the smaller size in a ported box comes a higher tuning. The tuning for this design is 23hz. Here is the graph of the 3.5 net cuft micro-cube vs a 4 ft sealed with 15" Dayton driver above and 800 watts
Green is micro-cube. 800 watts gets driver to xmax and you can use a inuke1000dsp to power it. Here is three other drivers in comparison to the Dayton
HereDayton 390HO - red
Titanic TS400D - blue
Alpine SWR15 - green
And Eminence LAB15 - black
kind of tough to see all of them because red, green, and black all produce about the same response below 40hz (of course max spl will vary based on usable xmax). same 3.5 cubic feet, 23hz tuning, 1100 watts.
So a small sub that can be cut from one sheet of MDF ￼, that would best a hsu vtf15 for this cost
400 bucks ￼ and your in business. Even with tuning at 23hz it gives usuable bass down to 18hz and it crushes ￼the sealed sub in 20 to 50hz zone. For music it would be perfect with little bass below 25hz. Now don't worry I'm not swapping out my minimartys for micro-cubes. But for those on a budget and limited space , I think this is a pretty good option. I hope there is someone out their who this can help.
Here is a martysub comparison