Right now with the growing amount of subwoofers on the market and free software that helps you design the perfect box, it is a great time to DIY a sub for you.  With the tools available, you can easily create a subwoofer that perfectly fits your needs.  But do you want a small sealed box or would you rather a much larger lower tuned box?  Everyone has their preference on this, but here is one that lays out why you might want a LLT sub (large and low tuned). 

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