I have 2 Alpine type R 12's. In a sealed box. I do not know if they are the 2 ohm or 4 ohm model. I am PRETTY sure they are DVC. My friend gave them to me and i don't know for sure. The back of the box has 2 red and 2 black outputs. One red and one black for each sub. I have no clue if they are wired at 4 ohms or 2 ohms and would like them wired at 2 ohms.
I want to make a ported box for them tuned at 32hz. If someone can tell me the dimension's of the box or lead me somewhere to figure them out.
After find out the dimensions and make the box i will take the subs out and find out if they are 4ohm or 2ohm and svc or dvc. and will need help wiring them at 2 ohms in the new ported box.
Well, each sub could be wired at 2 ohms, but the only overall impedance you can get is either 4 ohms or 1 ohm. This means you'd have to get either a 2 channel amp that puts out around 500RMS x 2 @ 2ohms, a mono amp that puts out around 1000RMS @ 4 ohms, or a mono amp that pushes out around 1000RMS @ 1 ohm. The cheapest route would most likely be getting a 1ohm stable amp such as the JVC KS-AR7501D or Polk PA1200. If you don't mind buying it refurbished you could also go with a RF Punch P1000-1bd from here. Or you can look elsewhere for a 1 ohm stable amp. As for port and slot vents, I think it's just a visual difference. Anyways, I don't think one has a benefit over the other. I'm not very good when it comes to building boxes, so I leave it to others come that department.
Better just hope they are the dual 2 ohm version, because there is no way to wire a pair of the dual 4 ohm version to a final impedance of 2 ohms. Far as the box goes, i would be glad to assist you with that. Knowing the model number would be a big help. You need to define at least 2 of the maximum box measurements, such as height and width, and then i could tell you the depth and what size port to use. If you have built boxes in the past, you might want to try a slot vent. It's more challenging to construct, so i'd say go with a port if you haven't done a lot of box building.
Yup we need the space constraints you are working with before we can design a box...
And assuming they are D2 ohm subs then they should be wired like this:
Ok i took them out. bad newssss.
They are dvc 4ohm.
The model number is SWR-1242D.
He had them wired neg to neg and pos to pos (ON THE SUB). Then another wire off the pos and off the negative going to the outside of the box.
i measured my trunk. The box can be 38 inches long and 15 inches high. the depth can be anything to aboutttt 25 inches...
I don't know the difference between a port or slot vent but either will be fine, I would like the vent or port to be tuned at about 32hz.
and since they can't be wired to 2 ohms i should look for an amp that puts out about 1000watts at 4ohms?
Thank you this helps alot. I think i'm going with getting a 1 ohm stable amp.
Either a
Rockford Fosgate Power T1000-1bd (2009 Edition) (wiring it at 1 ohm)
Rockford Fosgate Punch P1000-1bd (wiring it at 1 ohm)
Alpine pdx 1.1000 (wiring it at 4 ohms)
All of them seem fine and great quality to me, Now on to the box making!
SEE POSTS BEFORE TO GET BOX HEIGHT, WIDTH, AND PORT TUNING.
oh and ask for any other info you might need to help me with the box...
Thank you so much for the help so far!
The advantage of a slot port becomes apparent when you have a small box and need to fit a really long port inside. As for your box, i got a simple box for you that will have 3 ft net and a tuning of 32hz. Should be a great weekend project.
Use 3/4" MDF and build to an external measurement of 38" x 15" x 13.25". This is 3.35ft gross.
Use a single 5" PVC pipe cut to precisely 13.25" length. You have to mount it on the side of the box, as it's too long to mount on the front. Let me know if that's a problem, and i can suggest a right-angle slot vent.
I allowed an additional .036 ft of space for bracing. Using more won't shift the tuning much.
For the PVC pipe where do i put it on the side? I know it has to go behind the subs but will the hole make noise if it is right up against the trunk?
i don't know if you get what i'm saying but if i point the speakers forward instead of backwards i don't think the hole will be plugged.
The only rule to follow with the port is to allow a radius worth of room (2.5") between each opening and any obstruction, such as the wall of the enclosure or a body panel. Attempt to aim it towards a corner of the vehicle if your box placement allows. Bass is going to be pouring out of it so don't point it at a flimsy body panel, as it's likely to cause a good deal of vibration.
I picked up the board tonight. I'm gunna cut it tomorrow or wed.
Do i need to seal it with something special? or anything at all?
i like silicone caulk. it's cheap and easy to apply and does a great job. spread it into the corners with the back of a plastic spoon or find a method that works for you. A tip for sealing is to always put the back of the box on last. that way you can use the speaker cut-outs to reach in and seal the last piece.
Nevermind, I said something stupid, Sorry
The amps you picked are fine, but you might also consider the Sundown SAZ-1000D or Hifonics BXI-1210 or similar 1000-1200W RMS amps by Cadence, Soundstream, MMATS, Powerbass, US Amps, etc.
There have been a few previous threads on that.
Hope This Helps!!!
2002 Ford Focus Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs
Another Problem.............
No Where near me sell 5 inch PVC pipe... either 4" or 6"
I couldn't find it either. That's a pain. Using 6" is better anyway, or a pair of 4" ports would work. They would take up more space, so the box needs to grow a bit. Increase the depth to 14", and you can use 2x 4" ports cut to 18.75 inches, or one 6" port cut to 20". If you don't have the tools to make the ports exactly the same length, i'd suggest going with the single 6". if you don't get the length exactly right, it's not a big issue. Using 2 ports that are slightly different lengths can be a problem. They're not easy to cut precisely, and it's near impossible to get exactly identical lengths with hand tools.