Im looking to upgrade my 2 10s to a single 12 Sub setup and came along the alpine type R serie subs... does anyone have any goods/bads on these subs or something that would work just as well for cheaper. i think im leaning towards a more spl sub setup because i dont really need it for clarity so to speak since i have my highs amplified now..

Well i checked out their website to get some info on those subs, and it looks like it will do just fine for spl, and also for sound quality. Go with a properly built ported box, and have at least 300 clean rms watts to push it. I think that would sound good. I used to DB Dragrace, and i never really saw anyone use Alpine subs, but the technical info looks pretty good on them. The thing is, there are sooo many good subs out there around that pricerange, its hard to decide. I personally, love my aluminum cone Eclipse sub, its loud, clean, and since the cone is metal, it can dissipate mad amounts of heat to keep the voice coil cool when pounding on it. If you like to really turn up the bass alot, i would recomend a sub with an aluminum cone, it really helps for longjevity. I'm putting 2200 watts to my 1 15, thats rated for 1000, and I cant even come close to burning it up! Its one badd ass sub.. :)

well part of what i was thinking is all i would need to do is swap my 2 10s for the 1 12 and use the same amp that will push 300watts rms at 4ohms, as for a box for that sub.. where should i look to find it and what size would you recomend and priceing... and also I'd totally dig an eclipse sub.. but for one i dont have that much to spend much less get another amp, cause my next thing i want to change is my head unit with a premier model line of pioneer since ive heard they're pretty good. neways.. suggestions are always appriciated.

Well you could always buy a pre made box, but if you go that route, i would do a sealed box. If you want a ported box, have that custom built for you, to match the sub, because the ported box has to be designed (airspace, port diameter and length) properly to sound right. A sealed box is more "forgiving" when it comes to airspace the sub needs. Generally, a ported box is said to be 3 decibels louder than a sealed, and you said you want spl, so i would go that route. A custom built ported box might run anywhere from 85-175 bucks, but well worth it. You might even be able to find a premade ported box that you can cut the port to the needed length...Which model exactly are you looking at? Check out this link http://www.alpine1.com/html/D2_n_1_n_n.html
It gives a sealed box volume, but i do have a box building program on my computer if you need some ported box specs. Let me know..I'll have to check if my program has the specs for this sub in it..Opps, well it looks like the site has the Thiele-Small parameters in it, so i could plug in those specs in my program to give you a ported box size if you like.

i was looking at the SWR-1240D 12in with dvc... and yeah specs would work great if i decide to build a box for it or have someone make for me.. i have no idea when im going to get this sub if i end up getting it but once i have the $ i will... :-) oh and how exactly does the dual voice coil work and how would it be hooked up over the svc that most subs are..

oh and i the specs talk about "Bass Engine Ready" what exactly does that mean.

im accually thinking that i wouldnt be at that much of a loss to just use a pre-built sealed box since im not into compitition and i doubt id notice.. i dont turn my system up that much very often for fear i might break something in the car or such... ive gotten rid of most of my internal rattles which has been a blessing too..

Well the DVC sub has two 4 ohm coils, basically for amp hook up versatility. What are your amp's exact power specs? Is it a 2 channel amp or a 1 channel mono amp? Is it 1 or 2 ohm stable? If your amp is 2 ohm stable, then bridge the 2 channel to the SINGLE voice coil sub. This way, the amp will see a 2 ohm load when bridged(whenever you combine 2 channels of an amp, the amp "sees" half of the load put upon it). Or you could get the DVC and just run each coil to each channel of the amp. If your amp is 1 ohm stable(I don't think it is), then you could get the dvc, parallel the 2 coils to get a 2 ohm load, then bridge the amp on that to get the 1 ohm load. But i don't think your amp goes that low. If its not even 2 ohm stable, then get the DVC and run 1 coil to each channel of the amp. I guess i need more info on your amp, but generally, i like DVC's because of their versatility, if you ever decide to get a different amp.

Well if you want to make it simple, a sealed will do just fine. They recomend about 1 cubic foot of airspace, and a prefab box will work good also. but if you want that extra bass, a ported box will sound almost like you have 2 12's in there, assuming you have the same amount of power going to each. As far as the Bass engine, I'm not too familiar with it, i believe its a bass enhancement circuit devoloped by Alpine, just like a bass boost i guess. Check out their site and read up on it, looks like they have lots of info.

ok amp specs which aren't fancy..

kenwood 729s
http://www.sounddomain.com/sku/KENKAC729S

as far as i know it does 2ohms at 300rms along with 4ohms at 300rms bridged.. but its running at 2ohms right now i believe... doesnt do 1ohm and for my two subs they are currently running parrallel to get 150rms each at 2ohms.. 300rms total. so im hopeing that this is enough for the alpine sub and i guess i might as well get the dvc if possible that way if i beef up the amp or something then im set. i think for money sake ill stay away from the ported and just get the sealed... i really just want a lower bass thats punchy and clear.. plus im going to have to find a way to secure my box to the frame of the car for security purposes... cause im getting a little paranoid about that now and have been thinking of doing that for sometime... hmm so many decisions..

Well i'm not sure how exactly you have your subs wired, but it sounds like you have both 10's wired in parallel to the amp which is bridged to 1 channel right? If that is the case, then your amp is seeing a 1 ohm load! You can damage the amp like this! If your subs are single coil 4 ohm, then all you can do safely is wire each sub up to each channel, in non bridged mode. If both subs are wired together(both pos and both neg together), then your total ohms is 2. Now if you bridge your 2 channels together, the amp will see half of the load put upon it, so now the amp will see a 1 ohm load. Just a heads up man, if it is like that...A good way to secure the box that i have used, is to go to home depot, and buy some "L" shaped brackets, and screw them to the side of the box, and then to the frame, but with the tire well right there, you might be able to use metal straps or something like that..

i highly doubt that they are wired to 1ohm... but its been running like this since like june and no noticable problems... the subs i believe are 4ohm subs so i dunno... i guess i ought to break out a multimeter and find out...

you can check out some pics of my install(s) of my audio equipment here.. http://66.25.57.121:8080/photoalbum/cars/jason