If you take that DIY route keep in mind that you'll get full-range audio to the cabinet speaker. Our solution gives you extended bass because our amplifier has a built in low-pass filter that will maximize power transfer from the sound board to your cabinet speaker. Our kits are fully tested, completely compatible with any pin, and worth the extra money because they take all of the guesswork out of the project.
There is also a thread called "New Amplified Subwoofer Kits by PinWoofer" where you can read about some of the success stories.
We can ship internationally - happy to give you a quote!