Noob building ported sub box

[Ketsueki]

I have an Infinity Kappa Perfect 10.1 all the spec sheet gives you is a suggested volume of 1 cuft and port size of 3"x10.4" for 35hz for the box

however when i thought about building the box i was curious if where the speaker and the port were placed in the box effects how the subwoofer performs because i was thinking about building a box with internal demensions of 24"x10"x7" and placing the sub on the far end of the 24"x10" side of the box and placing the port on the opposite end in the center of the 10"x7" section.

also, this will be my first ported box, and the reasons why i thought i would build a ported box was for more SPL and lower notes, however i want to keep the bass tight, ive listened to a few of my friends cars subs, and they always seemed way too boomy

oh yeah, the music i mostly listen to is rock and techno and the amp i have is a rythmik A350

any input would be great, im trying to learn everything i can about subs so when i decide to build a good subwoofer i know what im doing thanks

 

[annunaki]

Is the sub going into a car or in the home?

In any case, to do a proper enclosure you need the T/S parameters. Manufacturer recommended enclosures are for the average joe who want bass. The parameters of the woofer will dictate what enclosure it actually will give the best performance in. (sealed, ported and what size and tuning frequency)

A 35hz tune on that sub seems quite high even for use in a vehicle.

As far as the ported enclosures being boomy it is probably a number of things that are causing that. A properly designed ported enclosure will easily rival any sealed enclosure for sound quality purposes, especially in a car. The added output from being ported is always nice too.

 

[Ketsueki]

the sub is going to mainly be in the home, i tried to play with winisd for a few minutes but i dont really understand what changes what when i was playing with it, also what hz should i shoot for, and does any one have any input i might need to know for building a ported box, ive always built my sealed boxes out of 3/4" MDF with out any internal bracing, however i always use liquid nails and then screw them together to make sure they hold and are air tight

also this sub is currently in a .625 cu ft sealed box, and it seems that the sub is bottoming out when it was hooked up to a 150rms watt amp, which i found kind of odd considering the spec sheet has it listed as a 350 rms watt sub, the main reason i brought this up was, does the size and design of the box effect the power handling of the sub? i dont want to worry about damaging my sub when i have it hooked up to a powerful amp..

oh yeah this is what i have for t/s parameters
Vas 32.13 liters
Voice coil resistance 4.11
Voice coil inductance le @ 1 kHz 2.96
Driver radiating area sd 53.4” squared
Motor force factor bl 16.64
Compliance volume 1.36 cu ft
Suspension compliance 189 um/n
Moving mass air/air load 166.71 gram
Moving mass diaphragm 163.01grams
Free air resonance (Fs) 28.35 Hz
Max excursion .56
Voice coil high 1.5”
Magnetic gap high .39”
Mechanical Q 8.83
Electrical Q .44
Total Q .42

 

[WmAx]

I have an Infinity Kappa Perfect 10.1 all the spec sheet gives you is a suggested volume of 1 cuft and port size of 3"x10.4" for 35hz for the box

First, a 3" diameter port is going to cause substantial compression around the tuning frequency. You need to move to a slot port, so that you can practically have at least a cross section with 30 square inches or more per driver.

For HT use, I would put this driver in a about a 2.9-3.0 cubic foot cabinet, tuned to about 19-20Hz.

This is a first rate driver, btw, with incredible low distortion and high linearity.

-Chris

 

[Ketsueki]

but its going to be used for music 99% of the time, and im also looking for some more spl then what my sealed box is giving me, also i dont know any thing about slot ports, have any information you could give me on this?

 

[WmAx]

but its going to be used for music 99% of the time, and im also looking for some more spl then what my sealed box is giving me, also i dont know any thing about slot ports, have any information you could give me on this?

WinISD has a slot port calculation option.

-Chris

 

[WmAx]

also this sub is currently in a .625 cu ft sealed box, and it seems that the sub is bottoming out when it was hooked up to a 150rms watt amp, which i found kind of odd considering the spec sheet has it listed as a 350 rms watt sub, the main reason i brought this up was, does the size and design of the box effect the power handling of the sub? i dont want to worry about damaging my sub when i have it hooked up to a powerful amp..

How do you know the subwoofer is bottoming out? The Kappa Perfects have a +/- linear 14mm movement, but can go much farther than that before failure.

In a ported enclosure of about 2.3 cubic feet, tuned to 25Hz, the 370+ actual watt output Adcom amplifier that I was using started to display clipping lights before any noticed distortion started from the drivers. I currently use a Behringer EP2500 on the Kappa Perfect 10.1 drivers. It produces over 600 watts/channel into 4 ohms, measured.

A 150 watt amplifier should start distortion/compression/clipping wildly before you can approach the Kappa Perfect limits in the sealed enclosure that you specified.

-Chris

 

[WmAx]

but its going to be used for music 99% of the time, and im also looking for some more spl then what my sealed box is giving me, also i dont know any thing about slot ports, have any information you could give me on this?

BTW, I am sorry, but I presumed you were using WinISD for modelling. If you do not already have this program, please get it from here:

http://www.linearteam.dk/

-Chris