Before i blow everything up......advice please!

[LoudCrownVic 5,000+ posts]

Ok, just built 2.7 cube per chamber box with 12" long 4" dia ports. It resonates like nothing I've ever heard (just practice box outta ply) and i have to place ports. Where should they go for max spl (speakers facing cab of car) how do I cut resonance a bit, what amp tweeks so I don't blow them up???

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[indosia 10+ year member]

The port should be 4-6 inches from the edge of the speaker. A subsonic filter can be used to eliminate the possibility of speaker damage. ANd use 3/4 inch mdf.

 

[InhumanAcura 5,000+ posts]

Everything he said, but use a subsonic filter if its ported otherwise it will surely mess them up. And fire the port and the speakers towards the rear of the car. The placement of the box in the trunk is often over looked. Move the box around in the trunk till it sounds loudest, i know you have a lot of room. There are some many things you can do to make it louder, its just everycar is different figure out what works best. Perfection comes with practice,

 

[LoudCrownVic 5,000+ posts]

Well, it was too late to help me, i just put the darn ports in where they looked the best (on the back upper outside corners) meticulously drilled holes for my phat 8 gage speaker wire, put the wire to the terminal, screwed the good ol' orions in and dropped it in my trunk. It fits like a glove and pounds way better than the old box.

I made it out of warped floor sheeting (not mdf (it was free, for crying out loud)) scrap pvc, a large box of screws, a tube of liquid nails, and some fiberglass insulation to cut the resonance. It's one of the more ghetto boxes i've seen but by far the most functional of the group. Total cost: 3.00 for the screws. Everything was re-used or scrap.

Anyway... I can't move the box around because it weighs about 65 pounds and is over 3' wide. But thanks for the advice on the subsonic, luckily i had one! :thumbsup :thumbsup

 

[the_flatlander 10+ year member]

we need pics

 

[InhumanAcura 5,000+ posts]

I would also like to see pics of this 3.00 masterpiece.

 

[LoudCrownVic 5,000+ posts]

****! Sorry guys, my camera is a piece of japenese **** and won't download pics onto my computer. I took them while i was building (almost twenty of them) but the ****ing camera no longer wants to talk to the computer.

To best describe the look of the box, it's a massive box (6.2 cubes total without the port volume taken out of it) It's as we speak naked except for an attractive swath of leopard print (ghetto innuendo) and the pencil marks, with two gigantic 4" port tubes on the upper outside corners, allowing a glimpse of the teal pvc sewer pipe i used. The inside has pulled apart strips of fiberglass insulation stapled here n' there on the inside, along with the port tubes which I drilled a hole through andd screwed to the side. Generally simple.

As to the added performance, my amp no longer cuts out on musical peaks (which i now think had something to do with the excessive pressure built up in the undercubed box), and it is i'd say 10db louder, and the response time has unbelieveably increased. Now I have sharp , quick clean bass, for 3 bucks. I'll get the pics somehow... Later. I'm busy this weekend.