new box only hittin lows

Just built a ported box holding 2 type r's for my truck using calc off this site for 35 htz.  Think it ended up being 5.7 cube ft. box with port 7x"12.5"x26".  Now I can't hit highs at all.  For reference, first note in "Put On" by Jeezy is hardly audible, then 2nd and 3rd quake, then the crossover kicks in on the 4th.  Looking to modify this box or even build a new one since it's only like $30 and would like to know where to start at on design.  This box only has one port on the side because I couldn't figure out how to calculate for one in the middle going to both chambers and because it seems like the subs would share the airspace better.  So any advice or help is appreciated.

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Jensen VM9214 Flip out, JVC 6x9's,Sony 6x9's Pioneer 6x9's, 2 Alpine Type R's in ported box, JL 1000/1 V2 Slash, Sony GTX6040 240 watt amp, Kicker CVR(Black), Alpine 500 (300) watt amp.

. . . Thats what a ported box is supposed to do.
the design gains SPL around the port's tuning frequency, at the cost of higher frequencies.
Try a SEAL box to get more of a FLAT level bass response.
BTW, the first note of the song is around 55hz. Check your crossover and slope because your system SHOULD be playing this note fine.

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It may not be the main root of the cause sounds to me like you possibly have some isses with crossover cascading from head unit and amplifier.  But I took a look at alpine's website and unless you are running 15"s that box is just shy of 2 cubic feet larger than what they recommend for the maximum vented box volume.  You have your port tuning right on but box volume seems a bit large.  If you have 15"s you are close but still over according to alpines manual.

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2008 Dodge Ram 1500
MECP Certified Advanced Installer CEA 191700

i bet hes running 10"s correct? judging by the port size, i say its in the crossover also, if the box was too large it will hit the higher end even louder, what program did you use?

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ac delco am radio and sparkomatic 40 watt sound exploder

I was toying with it last night and got it to hit highs.  Only problem is it only does it when the bass is all the way up on the radio.  Bass and sub all the way up and volume on 9 and it hits everything nicely.  Bass all the way down and volume on 20 and only lows.  I have a 240 watt 6x9 amp that I figured was drawing the power but I always thought the lows pulled more power anyway; plus, it is the same with the truck off as it is at 4000 rpm.  I have a Jensen vm9214 flip out. 

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Jensen VM9214 Flip out, JVC 6x9's,Sony 6x9's Pioneer 6x9's, 2 Alpine Type R's in ported box, JL 1000/1 V2 Slash, Sony GTX6040 240 watt amp, Kicker CVR(Black), Alpine 500 (300) watt amp.

What crossovers are you using and how are they set?

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Settings on the amp - LP on 80 htz with 24db slope, isafronic filter around 35, and center freq on 40.  And they are 12's which I've heard like big boxes. 

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Jensen VM9214 Flip out, JVC 6x9's,Sony 6x9's Pioneer 6x9's, 2 Alpine Type R's in ported box, JL 1000/1 V2 Slash, Sony GTX6040 240 watt amp, Kicker CVR(Black), Alpine 500 (300) watt amp.

def by 20 wrote:

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Settings on the amp - LP on 80 htz with 24db slope, isafronic filter around 35, and center freq on 40.  And they are 12's which I've heard like big boxes. 

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What high pass are you using for the main speakers, and what does the "center frequency" setting on the amp do?  Is there an EQ built into the amp?  As far as "12's like big boxes" this is completely dependent on the woofer.  You can't just slap any old woofer into any old box and expect it to perform properly.  Did you design the enclosure FOR the parameteres of the woofers, or did you just pick a tuning frequency and size and go for it?

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Support the12volt.com

my guess is the center frequency is for the built in bass boost on the amp.  surprising he's hitting low's really good with the infrasonic filter at 35 hz for 12's that could go way down.. I mean you're box is tuned to 35 hz  and you have a filter limiting bass below that

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2008 Dodge Ram 1500
MECP Certified Advanced Installer CEA 191700

I have heard that the Alpine Type r 12's like big boxes.  Some people have 3 cubic ft. boxes for a single and say it preforms great.  I have no external crossovers, only what's on the amp.  I haven't figured out the center freq. yet but I don't think it makes any difference on the sound in my set up.  The bass boost is on 0.  I just used a port calc. for a box that would fit in my truck; I tried the WinISD program but there wasn't a type r under the drivers.  Isn't it bad for a sub to hit under what the box is tuned at?

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Jensen VM9214 Flip out, JVC 6x9's,Sony 6x9's Pioneer 6x9's, 2 Alpine Type R's in ported box, JL 1000/1 V2 Slash, Sony GTX6040 240 watt amp, Kicker CVR(Black), Alpine 500 (300) watt amp.

Just found what center freq and Q was on the amp and it seems like it would help.  It allows the bass boost to boost only certain frequencies, hopefully I can boost the higher frequencies to level it out.  What i'm confused about is the fact that it plays highs with bass all the way up on radio but not with bass down and volume up.  This makes me think something in the radio is messed up.  I did the radio and box at about the same time so it's deffinetly a possibility.  Maybe I'll try my old $80 JVC hu

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Jensen VM9214 Flip out, JVC 6x9's,Sony 6x9's Pioneer 6x9's, 2 Alpine Type R's in ported box, JL 1000/1 V2 Slash, Sony GTX6040 240 watt amp, Kicker CVR(Black), Alpine 500 (300) watt amp.

With a lowpass filter set to 80, and a Subsonic set to 35, the amp is only going to play the frequencies between 35 and 80. 

I have 4 - 12" alpine type-r's and after building six different ported boxes for them, I really believe that these subs don't produce good bass above 50 hertz at all. I also think you have wayyyyy too much port area for those subs (I know its dependant on box sq.ft.) but i've had better results when I shrunk the port area down. I will be pulling my box soon and swaping it for my sealed 4-15" box which I thought sounded far better and louder to the ear.