okay so I have the basic frame, bottom, sides, front and back all together. comes to 9.875 cubic feet

there are 2 Kaption spl 1500's going in and they each get a kaption 700.1 for them. they will be firing upward in an '89 GMC Sierra extended cab and it will be geared for SPL competitions but also daily driven. port size is what I want to figure out so that its still listenable on most songs but be able to hit some decent numbers.

the truck was ripped apart and sound deadened yesterday and started on the box. we need to finish the box tomorrow most likely so some fast help is needed. thanks all!

 

heres the manual for the subs http://www.kaptionaudio.com/manuals/SPLManual.pdf

 

my opinion, extended cabs, sub forward, port drivers side.

anyway.

just looked up the specs on that amp, and 250rms per sub isnt going to be anything close to spl........

what are the dimensions of the box and ill check what port length you'll need. either way id be shooting for close to 100in^2 for port area, within that area.

 

the amps will do 710W RMS at 1ohm, which is what they'll be running at. heres the link for it http://www.kaptionaudio.com/testrepo...t%20Report.pdf

and outer diameter of box is 61X17X20. only using 3/4" but i'll be putting in bracing

 

hmm, the specs i pulled up may have been the wrong ones then. HOWEVER.

taking the fuse into contest.

50ampsx 14.4 volts= 720watts @ 1 ohm*efficiency of 70% maximum as they claim=504rms@ 1 ohm.

70% efficiency is pretty **** poor for a class D btw.

now something doesnt seem so right in their math now does it?

and on top of that, if you think you'll see a constant 14.4 in your car, you're crazy.



But back to your box.

17Hx61Wx20D

yields you 9.874 gross

after port displacement, you should be sitting at roughly 8.719

i wasnt sure if the 20" was your depth or height

so

if the 20 is your depth

and 18.5 deep X 4.5 high x 15 deep will yield you a tuning of roughly 35hz before bracing displacements.

if 17 is your depth
a port that is 15.5 deep x 5.5 h x 15 deep again gives you a tuning of roughly 35hz.

 

wow man, that helps a lot. we may be putting two more amps on these subs but its still up in the air. 1 out of the 4 amps may have a problem, thats why we went with the 2. tomorrow will be interesting.

 

its cool, ideally, if you havent cut the holes yet, id really do sub forward and the port at the bottom of the drivers side.



thats another one i designed a bit ago, but its still the general idea the same, just with the subs on the front face instead of the top.

with the subs firing against the seats in front it helps with loading to generate pressure against the cone, and similar setups have been used widely in bassrace.

 

so we did subs up, port up on drivers side. didnt spend much time tuning but what we have so far sounds great. thanks guys

 

meh, would have done forward. but whatever, atleast it works for you

just be careful with them firing up because that can cause the sub to unload pretty easily.

 

Is this Ben

What ever Happen'ed to you sent a ton of wall posts etc and nothing back