Does anyone have any experience with 18's?? how do they sound?? Im just wondering cuz I have never seen them sold online or in stores anywhere, are they used strictly for competition purposes? 2 10's= 1 12, 2 12's = 1 15, 2 15's = 1 18 ?? thats a lot of power..... what size amp would you need to run on average with one of those size subs.... cu. ft. must be humongous too.... just a quick question.....
hi,
they mostly are for competition purposes. I've seen one and only one and thats the 18'' and 20'' rockford fosgate hx2. they are hard to find. The run about eight hundred dollars a piece and the push some serious bass. The sound clarity isnt that great but if you want to win a competition, one of them will do the job. It wil run you another thousand to run the max rms out of the sub buy purchasing a 2400 watt mono rockford fosgate or alpine amp. Them amps are one ohm stable!!!
cool huh?
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bob
I currentlly have one 18" rockford fosgate hx2 in my car, we are still tweaking and tuning the box for spl, but the box know is built to factory specs and is hitting a 149.3 on a audio control mic. I actually bought 4 of these subs strat from the factory and can barely fit one with the box. I was going to remove the back seat and build a wall but I decided to use the vehicle for show. If you want great low bass 18's is the way to go. I'm am pusing the sub with a new Rockford Fosgate X7 mono amp and it sure does the job. I can't wait to get two in their.hehe
I have sold one 18" sub already and will sell the extra one I have if anyone is intrested. $500.00 plus shipping, I just know it will sit in my basement forever. I also have two Rockford Fosgate X1 2 channel amps for sale $350.00 a piece plus shipping. This stuff is all brand new in origanal box and not remanufactured, this came strait from rockford.
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The Clear Bra Guy
KCs premiere paint protection guru
the sad part is the rule of 3 in terms of output. if you double your drivers on the same amp (going from 1 sub to 2 on the same amp) you can expect a gain of roughly 3 db. Then to get another 3 db, you'd have to go from 2 to 4 drivers....sound being logarithmic requires logarithmic increases in equipment to get increases in sound 
b
not only the driver properties like hamilton said, but you cant even hear half what comes out of that sub. your feeling a lot more than your hearing anyway. if thats what you like more power to you. it just starts sounding like crap after awhile. id stick with 15's at the most, 18's just aint worth it. if you want a lot of boom get something like 4 12's and couple them. just make sure you understand phase before you go saying it doesnt sound right.
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Pete - SPL Enterprise Inc.