Sneak Peak at the new system

[negolien]

Originally Posted by S8track16

Won first in rookie 1 with a 143.2db at 41hz (TNE) and averaged 136.8db on music. Also placed first in bass race 139.9 due to the other competitor going over, first in street trunk db drag and third in woofer cooker 260.

Booya!!!! I guess that answers the question of your box build well done sir. Not only do you build a rocking system but you are always willing to help the other members and we appreciate it.

[tw0123]

Congrats Brandon good show bud!

[S8track16]

Thanks guys.

[S8track16]

[S8track16]

First of all, the alternator is working and voltage is stable at 14.6v.



When I first got the alternator back and installed it, voltage was once again at 17-18v meaning that the regulator wasn't working. Apparently, the light and sense plug that goes into the alternator only had a voltage of 5v rather than the 12v that is required to turn the regulator on. So I tapped into a switched power fuse and made sure the plug was getting the required voltage. Turned the car on, and the alternator was working fine.

I'm not sure if the plug only needs to be 5v for the stock alt or if I had a short in the wire somewhere. I figured I should let everyone know my situation in case you run into the same thing when changing to a high output alt.

[negolien]

Scary most people wouldn't know they would just put it on and expect it to work. Going to take mine over to orielly's next weekend to check it before putting it in. Not thinking it will catch something like your issue though.

[S8track16]

It is scary. If i didn't have a voltmeter in the gauge pod, I could have fried everything at 18 volts.

[negolien]

I do have that one in the distro think that would work?

[S8track16]

Ya it would show the voltage. You can also check the battery with a multimeter when it's first installed.

[tw0123]

Only thing I can see being an issue with the display being on the distro block is that it's behind you.... with a pillar pod or one in the cubby below the radio will help see a problem faster....

[Afugy]

Originally Posted by negolien

Booya!!!! I guess that answers the question of your box build well done sir. Not only do you build a rocking system but you are always willing to help the other members and we appreciate it.

To bad a box that was should have peeked at 30 to 32hz peeked at 41hz.

[S8track16]

Afugy, are you sure that the peak spl should be the same as the box tuning frequncy?

[AleroB888]

Originally Posted by S8track16

Afugy, are you sure that the peak spl should be the same as the box tuning frequncy?

Well, I'm not sure it should be the same. There are many possible alignments for those or most other woofers, for one thing. Some of them involve equalization of the extreme low frequencies to bring up the output at the box frequency. While it is possible in theory to get flat output below the driver's free air resonance (in this case about 40 hz), I would have expected a drop in output at the box tuning frequency in practice.

[Afugy]

Lower frequencies are harder to get greater SPL but to tune your box to 31 and peak at 41 is way off. I've never trusted any of those box programs. I've used them to make 3 test boxes and not once did they come out right when I tested them on Smarrt. Peaking that far off means the frequencies that you tuned your box to are being canceled out, from A. speakers being poorly spaced to your port (should cause it to be that far off though(note. if the box was firing into the trunk it would not matter because you turn your trunk into a 6th order bandpass)). B. Splitting the port cause air speed to exceed 10% the speed of sound and you're just getting port noise below 41hz.

[AleroB888]

The thing is, if in fact the peak bass output is around 40 hz and drops off below that with an f3 of about 28hz, this project result does appear to closely follow a known alignment. (I know the O/P used a higher box volume, but that can work better in practice).

If you compare the manufacturer's specs with the data in the chart, it tracks well with the predicted ratios for a No. 7 C4 vented box.

Total Speaker Q Value (Qts): .489
Free Air Resonance (Fs): 37.9 Hz
Equivalent Compliance (Vas): 27.38 liters
Suggested Box Volume (VB): 1.50³ ft

NO. 7. Type .....C4
Ripple.... 0.13 dB
f3/Fs........ 0.729
fB/Fs.......0.829
VB/Vas......1.372
Qt..............0.466

Not only that, I think for normal music input, around 40 hz is a good place to have strong output. I'll bet that system rocks! Anyway, the O/P built a solid vented system that has to be considered a success.

[negolien]

I concur sir. Do we know how they run these as far as what tone they were feeding it to begin with? I' am interested in how they conduct these now. It has me curious.