Help With Box Build Please

[majishin]

Hey guys I'm a total noob at this and have done a lot of research but always seem to come up short but I've had some ideas. I tried using Torres calculator and think I got what I'm looking for but don't understand how to translate the port over to the sketch I said screw it and jumped on sketch up with some general ideas. First off I'm running 2 Alpine type r 2 ohm 5th gen 1000w rms subs with an Alpine MRX-M240 amp in a pre fab shit box with center port tuned to 39hz 1.78cuft per chamber... not enough air movement at all and box tuning is all wrong I'm struggling now I have a 97 integra hatch and want to keep the use of the rear seats was thinking of a ported up firing box 30"w x 23d x 14.75h as I'd also like to utilize the privacy cover I'd love to be able to pull hair tricks off so was thinking of tuning it low but also don't want it to sound terrible maybe 28-32hz? Thanks guys I know I'm in the right place for this...

[RainStryke]

It takes a lot to get the hair trick, i'm not sure 2 type R's will get you there. You would probably need another two of those Type R's and they would need to be 15's. Unless you had two subs that could do about 2000w RMS each and you had the electrical set-up to do it.

As for the box, i'd suggest tuning to 30-34Hz, alpine recommends staying within 32-37Hz on a ported box. I tuned my box to 30.5Hz and I freakin' love it on my HDS312's... now I just a more powerful amp.

Maybe JoeX will stop by and give ya a build.

[majishin]

Hey thanks for the reply I know cone area and big box with low tuning is the key but it's a really small cabin I'm just trying to compete with my cousin who just got his hands on 2 jl w7s but has an suv I know those things are out of my alpine league but he bashes them every chance he gets hopefully JoeX will stop by and help me a bit

[majishin]

Ok so I've got a rear firing design still need to measure to make sure subs will have room for excursion I've got the port exiting through top rear 16"w across back wall by 3" now it's supposed to be 19 1/4 long or longer for lower tuning so from bottom to exit is 14" then another 5 1/4" extension on bottom or is that completely wrong?

[AstoSoup]

Just a thought, why not go with aero ports?? They cost a little more but are much easier to get the tuning you want.

[majishin]

It's a good thought as it seems less complicated but again I'm at a loss for knowledge in this area what size diameter and length should I use and how many also does placement of these ports make a difference?

[AstoSoup]

It's a good thought as it seems less complicated but again I'm at a loss for knowledge in this area what size diameter and length should I use and how many also does placement of these ports make a difference?

For Type-R's, I imagine one 4" per sub would be optimal. Length would depend on box size and tuning frequency. I have no experience with Alpine but from what I have seen, the normal tuning for these is between 35-40Hz.

Use this calculator once you have your box built... http://www.carstereo.com/help/Articles.cfm?id=31

Very simple to use. I would position the ports so they fire toward the back of your car, as well as the subs. Once you have the square footage of your enclosure, just enter it in the bottom calculator with your desired tuning frequency. I would say 37Hz would be a safe bet.... Your user manual should have some type of ported box recommendations, or you could find someone on here with Type-R's and ask them what they're tuned at, enclosure size, etc. Aero ports are very easy to use, only one calculation, length.

[majishin]

Thanks I've used that calculator and box is 4 cubes I think I'm going to tune at about 32 to start roughly 10 inches in length and 2 3" ports but there's no room to put them on the face with the subs firing at the back of the car box is limited to 30" wide so I think I'll have to fire ports up in the back of the box gonna build it on Saturday might get a couple pieces of pvc pipe and experiment with tuning a bit.

[AstoSoup]

Thanks I've used that calculator and box is 4 cubes I think I'm going to tune at about 32 to start roughly 10 inches in length and 2 3" ports but there's no room to put them on the face with the subs firing at the back of the car box is limited to 30" wide so I think I'll have to fire ports up in the back of the box gonna build it on Saturday might get a couple pieces of pvc pipe and experiment with tuning a bit.

2.0 cube per sub is pretty good. I would face the subs up and the ports back if you can, if the subs do not hit the trunk lid. Most every application sounds better with the ports firing forward, especially in a car. 3" will do justice, but I would imagine better sound from a 4".

[AstoSoup]

Thanks I've used that calculator and box is 4 cubes I think I'm going to tune at about 32 to start roughly 10 inches in length and 2 3" ports but there's no room to put them on the face with the subs firing at the back of the car box is limited to 30" wide so I think I'll have to fire ports up in the back of the box gonna build it on Saturday might get a couple pieces of pvc pipe and experiment with tuning a bit.

2.0 cube per sub is pretty good. I would face the subs up and the ports back if you can, if the subs do not hit the trunk lid. Most every application sounds better with the ports firing forward, especially in a car. 3" will do justice, but I would imagine better sound from a 4".

Firing backward**** Can't type today...