T-Line box for a Fi Bl 12

[Immacomputer 10+ year member]

//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif i used that **** too

It's not that it gives bad results, it's just not an ideal transmission line for most drivers. It will still have transmission line properties and most will still sound great, be very efficient, and have an effortless bottom end.

Another problem with that watered down method is that you're not compensating for the cabin of the vehicle (which is also a 1/4 wave resonator), which will actually make the line appear much longer to the driver and to the ear. They also don't have to be that large as you don't need to use 1xSd for the line area. My current transmission line in my car is tuned to 35hz (driver Fs is 24) and the line area is only about 44in^2 (Sd = 75in^2). It models poorly alone but when I take on the expansion and line length of my cabin, I have a flat response from 17-65hz with only a mild impedance rise at 22hz. The modeled and measured results were very close too.

 

[bigbud747 10+ year member]

FINALLLYY!!!! Got it metered last night.. And clamped at the same time to see what the new RockfordFosgate Prime 500 would really do. Ran through the lanes and did a 137.2 legal on the dash at 40hz i believe. I prob could've done a 138 but did have time to test and tune.. The kid that i built this box for also got the new Prime 500 amp and when we clamped it, it did 501 watts with a 5 ohm impedence rise..

Pics will be up later of the amp..

Question? Suggestions?

 

[bigbud747 10+ year member]

Here's the new Rockford amp.. Birthsheet said 545 watts, clamped it at 501 watts with a 5 ohm rise.. I'm very impressed with this thing..

 

[03silverado]

looks nice man

 

[bigbud747 10+ year member]

VIIIIIIDDDDSSSSSS!!!! With new amp..

 

[chief_bignut 10+ year member]

i built one of these for a pair of 8's i had and at first i was meh. but now after theyve had a chance to break in WOW they arent loud outside of the car but in my explorer they sound awesome and on movies ****! they get loud. im going to build one for a 15" ssd i just got cant wait you just motivated me thanks bro

 

[KyleBechtold 5,000+ posts]

umm... voltage.. you are going to kill your amp

 

[bigbud747 10+ year member]

umm... voltage.. you are going to kill your amp

That was the only time we played it with the truck off. When it's on it never drops below 13.. So don't worry, the amp will be fine. I'm very impressed with the Prime 500. Clamped it at 501 watts with a 5 ohm rise.. pretty **** good for a $160 amp.

 

[kyleorsini 10+ year member]

this makes me wanna do one for my 2 12"s to try it out but im willing to bet without doing any math the box would be huge //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

 

[bigbud747 10+ year member]

this makes me wanna do one for my 2 12"s to try it out but im willing to bet without doing any math the box would be huge //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

The way i would look at it is, if the Fs of your speakers are around 35, invision my box but double stacked one on top of the other, and you got a box for 2 12's. Port length will end up the same, but double your port area.

 

[kyleorsini 10+ year member]

Fs is 42.9 actually

 

[bigbud747 10+ year member]

Fs is 42.9 actually

Nice. So your box won't be quite as big as mine length wise, but it'll still be bigger with all the port area.. It looks like your line is only goin to be 6.6 feet long, whereas mine was a little over 8 feet long..

 

[bigbud747 10+ year member]