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Bryan90

12s in 4th order VS 15s ported

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Is it 7.5 by 7.5 square or a round port?. . . Where/what direction is the enclosure in the vehicle

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Round my bad and it's subs up port to the side there in a ext cab Silverado

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your enclosure is 4.01 cubic feet at 34.12hz before any sub displacement and/or bracing displacement.

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Are you just not happy with the output?. . .

Where are your settings on the amp set at? How did you set gain?

Edited by frogcase2002

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The output is good I just want more. I'm currently running a ppi p1000 but I just bought a saz 1500. I'm waiting on that and my ssf is set to 20 or 25 i don't use it. My lpf is at 45 to 50 and I set my gains by ear cause I don't own or have access to a o scope

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The output is good I just want more. I'm currently running a ppi p1000 but I just bought a saz 1500. I'm waiting on that and my ssf is set to 20 or 25 i don't use it. My lpf is at 45 to 50 and I set my gains by ear cause I don't own or have access to a o scope

 

Presuming your port is internal, no bracing, and no double baffle, your net volume is around 3.7ft^3 and 35hz tuning. The excursion of the driver is going to be excessive below the tuning point which is why one uses a ssf set a few hertz below the tuning point. Having it set 10hz below tuning is asking for mechanical damage--especially if you're switching to another amp with more power.

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I know about the ssf. It's never bottomed out that's why I don't use it but on the saz I definatly will I'm going to lower the tuning back to 30hz cause that's what sounded best to me. I actually figured the double baffle in to the measurements the box is really 32 x 21 x 16 but the top and side are double baffled. I actually bought the subs on Craig's list and the " custom" box they were in sounded like shit so I made it smaller and tuned lower and it sounded a lot better. How do you calculate port displacement?

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I know about the ssf. It's never bottomed out that's why I don't use it but on the saz I definatly will I'm going to lower the tuning back to 30hz cause that's what sounded best to me. I actually figured the double baffle in to the measurements the box is really 32 x 21 x 16 but the top and side are double baffled. I actually bought the subs on Craig's list and the " custom" box they were in sounded like shit so I made it smaller and tuned lower and it sounded a lot better. How do you calculate port displacement?

Calculate port displacement or account for it? If the former: (port length x port area)/1728 = port displacement ft^3 If the latter you can use a port calculator like here: http://www.the12volt.com/caraudio/boxcalcs.asp but it assumes the port is outside the box and not affecting the enclosure volume, if the port is internal then the port volume will reduce the box volume and the tuning frequency will actually be higher than what you calculated for. Give me a few hours to update something and I'll have a better calculator for you.

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I use the port calculater on car stereo.com which I assume is very similar to the 12volt.com one but I'm kinda confused so if I 3.7 cubes and want to tune to 30 hz and I come up with 30in of long at 7.5 round that changes the cubes of the box size so do you just play with the numbers til you get the right cubes for that tuning or is there a easier way that I'm over looking

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the sundown wont net you any audible output gains. theoretically it would 1.5db but you wont see that much.  

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I use the port calculater on car stereo.com which I assume is very similar to the 12volt.com one but I'm kinda confused so if I 3.7 cubes and want to tune to 30 hz and I come up with 30in of long at 7.5 round that changes the cubes of the box size so do you just play with the numbers til you get the right cubes for that tuning or is there a easier way that I'm over looking

 

Here you go: http://box.bitpusher.in/enclosure/?page=portlength

 

If your browser tries to block the site just ignore it and proceed.

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Oh and what the teddy bear for?

It's a joke. Regardless of what's in the box you need to account for it.

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