I want the truth about 12s

it depends on what type of sub you want.. also..

like either a SQ or SPL

I agree. If you listen to rap, R&b, stuff with alot of bass then you probably want to go with a 12" or 15". If you like rock metal, etc, then you would want a 10". I perfer SQ rather than SPL, but having a happy medium I find is the best, this again is where setup and design is a big factor.

also the cash your willing to spend, the power you will be supplying it with an the amount of space in the enclosure.. also the type.

Thats where places like eBay and local classified ads come in. You can get an awesome used 500-1000 watt mono amp like a Hi Phonics (eg.zeus) or older zapco for between $100 and $200. There are many older amps that can kill anything new for a fraction of the price. I wouldn't buy your speakers used though.

As an example, I just put a smaller system in my winter beater for about $900. This is what I have, where I got it and what it cost.

Two 7" Fosgate TFT LCD Monitors $110 eBay New
Audiobahn DVD Player $80 eBay New
Clarion dxz745MP Head Unit $130 eBay Used
Infinity 6010CL Component set $60 eBay New
Alpine Center Channel $90 eBay New
Zapco AG 250 mono Amp $100 Friend Used
Alpine 4 Channel 50X4 RMS $85 Classified AD Used
Audiobahn DVC 12" Sub $60 Old Stock New
Fuse Blocks, Wire, Mounting kit, RCA $100 Local Store/ New
Princess Auto
Remote for Clarion $8 eBay New
Zapco Line-Driver $75 Friend Used

Total $898


I collected this over about 5 months whenever I found a good deal. So I would say that you can have an awesome system for an awesome price. I love this setup, although when I find the time and the parts I would like to change a few things like the 4 channel Alpine amp (lacks huge in power, would say more like 25 X4 RMS) and infinity component set.

sounds like you got a nice system

About the 10s tighter then 12s deal. In a good box with a proper amp, you can BARELY tell. My suggestion has always been find the subs you want in the enclosure that suits your style of music (sealed is great for thump and kick while ported better suited for boom). Next find the RMS of the sub and use a Class D amp that's rated RMS is slightly higher. Remember to check RMS not peak wattage on the amp. And also check the amps lowest ohm capacity. Lower ohm load allows the amp to flow more wattage with the downside being slightly less woofer control (your bass will not be as tight, again a properly matched box can help compensate) and heat... most amps have thermal protection but constant high temps will decrease the amps life. Sorry for the long post. My preference in amps/subs are Memphis. 2 12s in a sealed enclosre with an 1100 watt amp (2 ohm load) make my eyes blur and my teeth rattle. Way more bass then needed for regular use, but fun to have on tap

RMS (Root Mean Square) is basically what the sub will handle during regular use and the peak is what it can handle for a one second interval without blowing. And on the amp side, the RMS is what it will put out during normal use and its peak it what it can hit for 1 second.

Which is why SPL champs use the "burp" LOL That 1 second blast of bass.

you really should pay attention to enclosure design, subwoofer frequencie response, and a Big variable is the sound your looking for

i didn't really take the time to read all of the other posts, but i really like jl audio. they require very little air space and produce a lot of power. but i will be getting a set of earthquake shallow subs. look into them. they only stand like 4" tall. and with my truck being a reg cab they will work like a champ. i got an eclipse and put it in for now but when i got it i didn't expect it to be so tall, so i will just put it in my s.u.v.