The cone on a 15" woofer is much bigger, and is is atleast 2-3x as heavy as a 10", as the middle area will need more reinforcing. Weight= slower responce, even with more power over a smaller woofer. Yes they do move much more air, but that'* not how sound quality is made. 15'* can sound good, but they take more work/power then a 10" will, and it won't have nearly as flat of a response as a 10" will. Likewise geting low tones from smaller woofers isn't hard, but getting them at a level you may think is good may be. In my room I have a pair of B&W speakers, with 7" kevlar woofers. They play well below 40hz, and are VERY clean while doing so, I've never distorted them at any volume, acceptable or too loud.

The ports on my Hi Fi speakers are flared a lot, and have dimples like a golf ball to let the air flow smoother and quicker. They've never chuffed by huge bass hits AT ALL.

Back on track, yes you can have good SQ 15'* but not in the realm of 99% of car fi buyers, and they are just impractical. Why takeup 2x as much room in the trunk to have a bigger woofer?

Skip the cap, it only keeps your headlights from dimming really, your battery will still get the same juice sucked out of it (actually more with the cap), and witht he power you'll be running i don't expect anything bad, they'll only dim when at idle, once i get above 1000-1500 RPMS my dimming goes away.

i still have to disagree, there are many other things that affect weitght and how far a speaker moves, how much air it moves, power handling, and things like this, size by itself, doesnt determine sound quality, or even how a speaker will neccesarily act

Yes but you can only compare different sizes between the same lineup by a company. No 15w0 will sound better then a 10w0, no 18" adire will sound better then a 12" etc.

When I went up to the shop, they guy seemed pretty sure that 1 15 would be better than 2 12s. Also, he played them and they were pretty tight, as opposed to the alpines he played next.... those things were loose! :o

which alpine subs? i think the type r 12s are a pretty decent SQ sub for the price.

I am not sure they were either the r'* or the *'*.... I forget which ones he was saying they were. The guy seemed pretty damn partial to JL audio.... he compared the lowest grade JL 12w0 to a medium grade alpine 12.... no contest the 12w0 was soo much of a tighter sound. Then he played the 15w3, and I was pretty much sold, now to save over a grand....

i plan on keeping my system all alpine...by adding on a type r 12 and a 500/1 amp. Alpine type e'* and type *'* seem to be junk, but i had a type r 12 before and really liked it.

if i wasn't trying to match my whole stereo setup i'd probably go jl now. but ya live and u learn right??!!

I would definatly go with the type R if you decide to go alpine. The guy wasn't rocking all of alpines stuff, he said that he accually runs an Alpine HU and components with a JL audio amp and a 13.5 w7

If I may ask, why stay with all alpine, its not like JL won't work with alpine. Is it just a personal preference?

kinda hoping for a "show" type setup when done. nothing special....just hu, components, 6x9s, 4 channel amp, sub, and mono amp. got some ideas for a pretty sweet custom box that a buddy and i will build. just wanna keep it simple and clean...and kinda a personal preference on all alpine.

just be kinda neat to say i'm running type r speaks all around with v12 power running em.....but maybe i'm lost in my own little world

Type R are nice, he may get better bonuses or a higher commision. Try all of your music in their CD players, the stuff you listen to, your cd'*. And make the sales guy shut up.