I must admitt further to my post....
Visonik, Boss, Dual, Pyle, Freeway, I don't sell, or want to sell, and here's why. It's all eye candy, and at the end of the day, they will not hold up to a better sub, and I can't afford to help in the warranty department... You can make that boss sub loud, and in the right box it "could be??"as loud as a sub that is twice or three times the money with the same power. But give that boss more power and it comes apart, sounds crappy, and will just plain burn out. So spending more money for a sub the first time is almost always the better value. I find that the companies mentioned above are starter product, and after you spent $200.00 dollars playing with the "entry level" subs, you'll see that you are ready for something better. Don't get caught up in fancy looks, the W0 or W1 from JL don't look like much, but they really set the stage for SPL as we know it today.

 

box rise plays alot in spl as well , impedance is very important , also the type of vehicle is a huge factor