[SUB] svs sb 1000 or create DIY one?

Hi Guys, I have got klipsch the sixes active monitors. There is a possibility to connect the subwoofer. I have decided to get one. There is no enough of bass for me especially in the movies.



Everyone is recommending: SVS SB 1000 which is like $500 price tag. My room is like 25m2.



Would be possible to create better subwoofer by myself in this budget?(500$)

It should be active. I have almost zero DIYAudio experience but I'm very open to gather some.
 
It would be (barely) possible to create a "better" (as in louder) subwoofer for $500 in parts, but it would be hard to beat the size, features and warranty, and would require a lot of DIY audio experience. With zero experience, you may also be lacking tools, buying or renting them could easily put the budget over $500.

Factor in your time ("priceless") learning all that goes into a good design and build (weeks), and then the time in building (days), and the time cleaning up during and after the build (hours), and then you have the answer.
 
Ratcheting up from $500 to $800 gives DIY a little more "wiggle room", but again, for a similar sized sub would be hard to beat the SVS SB-2000 pro if your build/test/tune time is considered as part of the cost.

Also to consider is the potential for destruction when developing DSP settings, figuring out "how much is too much" compared to "what will be safe for any input" can result in a smoked or torn-up driver, which takes any cost savings down in a hurry.