[sam_b03]

sealed or ported?

I have a 95 nissan 240sx that was a former drag car. I got and want it to be a little more user friendly and basicly just a toy. It has a 10 point roll cage that I don't want to take out because it has 430hp chevy 350 that could potenially twist the chassis. The fuel sell is in the trunk so I will have to build the box in side the back seat area. I am wanting to go with a more SPL oriented build and was thinking 2 sundown SA15's on a MB Quart 1500.1 at 1ohm would probably be enough for me. I know that ported gets loader, but the only ported boxes I have been around were Qlogic store bought boxes that you heard alot of "whooshing" from. Most of my friends in High School (years ago) just plugged their ports with balled up socks. It sounded pretty bad. The worst of both worlds. it was a chocked ported box or a severally leaky sealed on. That is the extend of my experience with a ported box so It wanted to ask the experts before I made my decision.

This isn't going to competion. More of a rolling juke box at the lake. Definitly want a musical sub. Thinking about selenium 8's in the doors. Haven't looked that much in too tweets. Going active with eclipse 7200 MKII. If that effects anything.

 

[Ray21]

I like vented better than ported... almost as much as I like bass reflex.

 

[tornaido_3927]

Vented = ported

 

[adrenalinejunkie]

Both

 

[sam_b03]

sorry kinda tired when I post. I ment sealed or ported.

 

[tornaido_3927]

Haha, fair enough..

My vote goes to ported, based on the fact that you want it to be SPL biased.. There's no reason a ported box can't sound REALLY good as long as the box is built properly. They are more difficult to build than sealed boxes as port and box size needs to be well designed and properly built for decent results.

Searching here or on Google should net you a bunch of posts on ported Vs sealed for a wide range of subs as well as speakers in general..

 

[sam_b03]

I hear about them alot. I just don't have much personal experience with them, and what I do have is poor examples. I just don't want to hear the port breathing very time the bass hits. It will at most be 3 or 4 feet from me. If it was going in the trunk it would be a no brainer. I have the space. I will have to get creative when it comes to building inside the car.

I have access to a the programs to make a good box and a good carpenter. I am not looking to half ass this project. I am not sure how I will mount the box. maybe fiberglass a mount since the back seat is no where close to even.

 

[tornaido_3927]

That's good, if you have the programs and skills you should do well

Stopping the port from making the audible breathing, or chuffing, is pretty simply a matter of not making the air pass through the port at too high a velocity. Not sure which box program you have, but my one shows me the vent air velocity of the port.

The threshold for hearing the chuffing is around 35m/s, although generally you don't want to actually have the port get near to this number. It can take a bit of fiddling around with port diameter and length vs tuning, but with your skills I think you'd be able to build yourself a decent ported sub without the poor qualities of ones you've been subjected to