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IDSkoT
11-16-2008, 07:58 PM
Well, some kids wonder "ZOMG, WHAT BOX SHULD I USE?!?!?! IZ PORTED TEH BEST?!"

Well, I used WinISD Alpha, I used a pair of Audiopipe TXX-15 drivers, with default specs.

Here are said specs:

Sealed:
7.341 cuft

Ported (AKA Vented):
15.748 cuft
tuned to 22.97 Hz

4th order Bandpass:
Rear chamber: 6.987 cuft
Front chamber: 4.179 cuft tned to 40.99 hz

6th order Bandpass:
Rear Chamber: 3.531 cuFt tuned to 20hz
Front Chamber: .925 cuFt tuned to 63.46 Hz

Passive Radiator:
7.341 cuFt using a 12" Passive Radiator (http://www.parts-express.com/pe/showdetl.cfm?Partnumber=295-496) from Parts-Express



Now, the color chart:
Sealed: Yellow
Ported (Vented): Grey
4th Order Bandpass: Orange
6th order bandpass: White
Passive Radiator: Purple (It could be pink.. I'm kind of color blind)

http://img.photobucket.com/albums/v714/TwistedShot/chart-1.png


For your hard-core people out there, this was done in WinISD @ 85* F, 75% humidity, and 101.325 Pa...

Please note:: As you alter the tuning frequency on vented boxes, it becomes more "peaky", and won't roll off that flat. This goes the same for the bandpass boxes, as well. If I changed the 6th order bandpass box so the front chamber is tuned to 100hz, the whole line shifts and it has nearly the same response as sealed/vented/passive radiator in the 40-50hz range, and peaks really high in the 100hz range.


Now, with that said, and the chart shown, note, this is just Db gains based on a computer model, and does not include the car's involvement...
As most will tell you, it all depends on your car and your application.

But, I just decided to put this together real quick to show each box's relationship to each other in perfect conditions.

Trey803
11-16-2008, 08:00 PM
this is not saying much. This type of test is driver dependent.

IDSkoT
11-16-2008, 08:01 PM
this is completely relative to the drivers being used

Yeah. I know. That's why I labeled the drivers. Like I said, it's just a relation based on the drivers I used.

snb778
11-16-2008, 08:04 PM
interesting... would have guessed the 4th and 6th would have higher peaks than the rest

IDSkoT
11-16-2008, 08:09 PM
Since Trey pointed out a very good point, I decided to do another "test" with a pair of IDQ10's. I used these drivers 'cause someone I know is ugnna make a build with them soon, so I thought, kill two birds with one stone...
I also made the lines thicker so it's easier to read.

Color chart is the same:
Sealed: Yellow
Ported (Vented): Grey
4th Order Bandpass: Orange
6th order bandpass: White
Passive Radiator: Purple (It could be pink.. I'm kind of color blind)

http://img.photobucket.com/albums/v714/TwistedShot/chart2.png


Now, the specifications of the boxes:

Sealed:
2.428 cuFt

Vented:
3.982 CuFt @ 24.5 Hz

4th Order BP:
Rear Chamber: 2.343 CuFt
Front Chamber: 1.792 CuFt @ 50.53 Hz

6th Order BP:
Rear Chamber: 3.531 CuFt @ 20 Hz
Front Chamber: .925 CuFt @ 63.46 Hz

Passive Radiator [Using the same Passive Radiator as the first "Test"]
2.285 @ 30.36hz




Like Trey said, it is really determinant on the driver.

Rashaddd
11-16-2008, 09:25 PM
this is pretty useless information

IDSkoT
11-16-2008, 09:40 PM
this is pretty useless information

Not really. It shows each box's relationship to each other in terms of DB output. The IDQ10 is pretty good all around, I could do some other drivers if you want. Most of the time it's the same results as the first chart.

Rashaddd
11-17-2008, 12:55 AM
Not really. It shows each box's relationship to each other in terms of DB output. The IDQ10 is pretty good all around, I could do some other drivers if you want. Most of the time it's the same results as the first chart.

It would be much more beneficial to explain their relationships and potential advantages. With this, the stupid people are going to look at it and pick the curve they like most, and conclude that is the best kind of box for their goals. The smart people will realize it is useless, and most already have a much more solid foundation of knowledge in terms of the differences between the box types.

The people inbetween don't exist because this is CA.com

photocrazy8
11-17-2008, 02:13 PM
its useless because that has nothing to do with car audio. it just models a drivers output and proformace in ideal situations which cars are not, each having different cabain gain etc...

photocrazy8
11-17-2008, 02:16 PM
also your average person does not care where the roll off occurs, they just want a Chebyshev allignment and max output...

Immacomputer
11-17-2008, 03:09 PM
interesting... would have guessed the 4th and 6th would have higher peaks than the rest

That's just the frequency response of the transfer function. The actual peak output of each enclosure will differ quite a bit. Each enclosure has a different efficiency to it and those graphs don't factor in sensitivity (and neither do the SPL graphs winisd will give you).

groundpound4200
11-17-2008, 04:01 PM
do not.... I repeat...DO NOT build a bandpass box based on the estimated frequency reponse of winisd. It will not sound right :fyi: Don't ask how I know :crap: