Cerwin Vega speakers can be very loud indeed. especially the Stroker. But they require alot more power than almost any other subs on the market. Yes they have won many sound offs and spl competitions. They are in the league with the JL W7, Resident Engineering xxx, Brahma, Kicker solo X 18", Juggernaut, MTX Sledgehammer and new Jackhammer (by far the loudest sub ever made, requires a minimum of 6000watts to move it!!!).
The setup is what makes them so loud. you need a ported box that is of the right specs for the sub, as well as designed for the internal volume of your car (no box sub combo will sound the same in any other car because the air space inside each different vehicle is different as well as the shape of the vehicle). You need massive amplifers to achieve high spl (for a Cerwin Vega Stroker at least 2000 watts RMS, NOT PEAK!!!) as well as a solid base electrical system with high grade batteries like optima gell cells and a high output alternator so the amps have the voltage required to push high watts to the subs. You will also need capacitors to match, 1 farad per 1000watts peak power. You will also need to sound deaden your vehicle to achieve high spl scores. I have seen cars with concrete poured into the body panels to reduce the resonant frequency of the car on the extreme side, as well as nylon straps to hold the doors shut on a chevy s10 that had 4 15" Strokers with over 8000 watts running to each one and 16 amps in the bed with 16 batteries as well. Not a system you would build for everyday listening by any means but very VERY loud), but most people use plain dynamat applied in 6-7 layers.
You may also look into the Juggernaut line of subs, I had the privelidge of learning car audio install practices from the former world record holder for spl. He had a ford pickup with 2 quad 0.7 ohm voice coil 15" Juggernauts with over 20,000 watts RMS being burped (the term used in a spl competition when you play a 2-3 second test signal) to them and hit 171.2 DB. He had to put lexan windows and 10 layers of dynamat as well as strap the doors shut to keep the vehicle together!
you will also need a high end reciever to provide high grade signal to the amps, and could also use a line driver to up the voltage of the signal out of the reciever as well.
0 guage wiring is a must as well as the best RCA leads you can find.
The Cerwin Vega Stroker is an extremely powerful sub when it is applied correctly. On the down side the sound quality of the Stroker is very poor in comparison to most subs...Cerwin Vega went for max volume over quality.
The 15' shouldn't cost you more the about $450, an amp to push one will cost anywhere from $1500-3000 from US amps, JL Audio, or the new 3000 or 6000 watt JBL/Crown amps(the best for the stroker if you only want to use one amp, runs $3500-6500, requires dual 0 guage power and ground leads, at least two yellow top optima batteries, 10 farad capacitor and a 200 amp or better alternator). Battery only $150. Capacitor anywhere from $100-400. wires around $250 for power, ground, signal and misc. other wires like remote lead and connectors. You will spend about $350 on enough dynamat to control the vibration in your vehicle.
The Stroker is a great sub for competition, not so great for daily listening. If you want something that you can bump to rolling around town you should try the JL w7, the MTX Sledgehammer or the Resident Engineering XXX. Those will give you much better quality and still be loud as all get out.
And just so you don't think I am blowing smoke at ya...
I have One 12" JL W7 (the 8th one to be delivered to the midwest! I was on a waiting list for 16 months!) in a dual ported enclosure made specifically for my car by JL Audio (cost me about $600) with 1760watts RMS running to it from a modified (hotrodded with larger capacitors, heatsinks, and transformers) MTX 1501D mono sub amp, a Phoenix Gold PLD1 line driver giving it 8 volts input signal from a Kenwood Excelon Head unit, JL XR 6.5 Components in front and back mounted in custom totally sealed enclosures IN the doors and rear deck, powered by an Alpine 110watts RMS x 4 4ch amp, a 15 farad capacitor, 2 yellow top optima batteries, dual 0 guage power and ground leads, I made my own RCA leads from 8guage gold wire with nickel and rubber insulators, 7 layers of Dynamat Extreme plus all holes in the trunk and door panels are sprayed with expanding foam, and an ohio generator 210 amp high output alternator. It hits about 140db on a regular basis, I have hit 158.7 at a show about 2 years ago. The W7 is also a very accurate (arguably the cleanest and highest sound quality sub on the market) sub that can play any kind of music. Total cost of the equipment was around $4600 and if I were to have had a professional shop install it all (I did it all myself I have a degree in Mobile Electronics and have been an installer for almost 8 years) the total would be around $7500.
hope this gives you an idea of what the Strokers are all about. All the other Cerwin Vega subs are pretty mediocore in my opinion. Keep in mind what I like may not be what you like. Car audio is all about the listener. It has to sound good and be loud enough for you!
If you have more Questions or would like help building a system for yourself feel free to email me at INDYCARINSTALLER@YAHOO.COM.