2 18 - Box question

[winkychevelle 10+ year member]

Main problem with both facing up is there is no reflecting wall.

we did a box a while back for 4 15s. The guy wanted a solid shelf over the box so we laid a board over the top at like a 15° angle and basically created a 6th order bandpass but in simpler terms we added a loading wall before redesigning the box

 

[Buck 5,000+ posts]

so your meaning fire the the port up as far back in the blazer as I can with out it directly firing on the hatch?

Like this:

 

[bgowdy 5,000+ posts]

Main problem with both facing up is there is no reflecting wall.
we did a box a while back for 4 15s. The guy wanted a solid shelf over the box so we laid a board over the top at like a 15° angle and basically created a 6th order bandpass but in simpler terms we added a loading wall before redesigning the box

so how do people make them work with out adding that on to it

 

[Buck 5,000+ posts]

Main problem with both facing up is there is no reflecting wall.
we did a box a while back for 4 15s. The guy wanted a solid shelf over the box so we laid a board over the top at like a 15° angle and basically created a 6th order bandpass but in simpler terms we added a loading wall before redesigning the box

It depends on the woofers, the tuning, port area, height of the box. Most SUV's hatches comes in over the port if it's all the way back, and you will get some loading from that, not as much as firing rear. That's where port area and tuning play a big part.

 

[bgowdy 5,000+ posts]

It depends on the woofers, the tuning, port area, height of the box. Most SUV's hatches comes in over the port if it's all the way back, and you will get some loading from that, not as much as firing rear. That's where port area and tuning play a big part.

the more you say the more it almost sounds like sub up port back lol... but anyway I think I see what you mean from that box design. but im going to use aeroports and the

 

[winkychevelle 10+ year member]

Screw it get some 24inch passives built up

 

[T3mpest 10+ year member]

Screw it get some 24inch passives built up

Not sure if anyone makes those anymore. I believe Exodus audio did for a short while, or it was in the plans and never happened, IDK. Since he's only running OA18's he "may" be able to get by with 2 18inch passives. Most passives won't have double the throw of the woofer, closer to 75% more. He could get by with 3 though if he side fires one. I have a setup like this right now and it has NO loading issues whatsoever, it's actually too loud at tuning if anything. I have 2 facing rear and one on the passenger side.. You def have to get the box secured to the vehicle though. I had a box that's a sheet and half of mdf with a 60lb sub on top and it still moves around the car when the bass hits.. Tuned at 30hz does really well down to 20hz.

Anyway as buck said, if your going to do port up I'd run it along the back so it's still getting as much loading as possible off the rear.

 

[bgowdy 5,000+ posts]

[quote name='T3mpest']Not sure if anyone makes those anymore. I believe Exodus audio did for a short while, or it was in the plans and never happened, IDK. Since he's only running OA18's he "may" be able to get by with 2 18inch passives. Most passives won't have double the throw of the woofer, closer to 75% more. He could get by with 3 though if he side fires one. I have a setup like this right now and it has NO loading issues whatsoever, it's actually too loud at tuning if anything. I have 2 facing rear and one on the passenger side.. You def have to get the box secured to the vehicle though. I had a box that's a sheet and half of mdf with a 60lb sub on top and it still moves around the car when the bass hits.. Tuned at 30hz does really well down to 20hz.

Anyway as buck said, if your going to do port up I'd run it along the back so it's still getting as much loading as possible off the rear.[/QUOTE]

yea i get what he means. but it confused me because he said not to have it load off the hatch? That part i didnt understand. @Buck;

 

[bgowdy 5,000+ posts]

@dbeez; figured id get your opinion as well

 

[winkychevelle 10+ year member]

so how do people make them work with out adding that on to it

I never said it wouldnt work without it I was just giving u an idea so that if you box doesnt perform you would have something to try for the cheap.

As far as the 24 inch passives I was generally thinking to contact psi, splaudio, or tantric and have them built from eother the 24inch frame tantric uses or the 21inch from incriminator uses. Both would be expensive as hell though

 

[bgowdy 5,000+ posts]

I never said it wouldnt work without it I was just giving u an idea so that if you box doesnt perform you would have something to try for the cheap.
As far as the 24 inch passives I was generally thinking to contact psi, splaudio, or tantric and have them built from eother the 24inch frame tantric uses or the 21inch from incriminator uses. Both would be expensive as hell though

im really not trying to get in to passive radiotors honestly. i wouldnt know were to start

 

[bgowdy 5,000+ posts]

bump

 

[bgowdy 5,000+ posts]

ttt

 

[bgowdy 5,000+ posts]

Ttt