bandpass box?

[gunz4me2 10+ year member]

wait a sec. you said at 1st it was a RF 1500, not a RF 500. so you traded 2subs and a 50watt less amp. (possibly more depending how it's wired) now you're wonderng why it's not as loud? the deal was worth it if you got a RF 1500, not worth it with the 500.please tell me i read something wrong here.

//content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif A 50 watt difference generally isn't detectable by the human ear when we are talking about the difference between 500 watts and 550 watts!

 

[xj-jeep 10+ year member]

Alright i pulled a speaker out. they are jbl gt1200d's. Does anyone know a good size for a ported box for these things? I got them hitting pretty hard now, but the box sounds like ****... it rattles and don't hit lows or highs, just low mids pretty much...

 

[chillin 10+ year member]

Alright i pulled a speaker out. they are jbl gt1200d's. Does anyone know a good size for a ported box for these things? I got them hitting pretty hard now, but the box sounds like ****... it rattles and don't hit lows or highs, just low mids pretty much...

Thats what bandpass boxes do...unless they are built properly to the specs of the sub (which prefabs never are)

 

[chillin 10+ year member]

Here is a page with some specs. dont know if they changed over the years or not, but it should help. from this, you should be able to gett someone to design you a box.

The Subwoofer DIY Page v1.1 - DUMAX Measurements

 

[xj-jeep 10+ year member]

Alright cool thanks man. Ill see if i can get some plans and build a box for it and then see if i can get someone to buy the junk bandpass on craigslist lol

 

[iLL Ridge 10+ year member]

I had A BANDPASS box for 2 -12" old mtx thunders. Hit hard at 40-45, but that was all. Didn't sound too good.

 

[GotSPL?]

They are great!

 

[xj-jeep 10+ year member]

I have no idea how to tell what cubes would work good with this box.. If anyone could help that would be sweet, here's some specs on the speaker. http://manuals.harman.com/JBL/CAR/Boxes%20and%20Parameters/GT1200.pdf

 

[gunz4me2 10+ year member]

Looks like JBL wants 1.2 cubic feet per 12 sealed or 1.8 cubic feet per ported 12 tuned to 30 Hz. I'd model it up for you, but I have to key the stuff into bass box pro and I am feeling lazy right now. //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif I'll post back later.

EDIT: Bassbox pro isn't that far off from JBL's recommendations. Basically it recommends 4.5 cubic feet net ported tuned to 29 Hz with your predicted F3 at 41 Hz.

Sealed, BB Pro recommends a smaller than usual enclosure for the magical .707 Qtc alignment at 1.357 cubic feet net for both 12s. I would NOT recommend a sealed enclosure this small for those 12s!

 

[xj-jeep 10+ year member]

Alright sounds good man thanks for the help

 

[xj-jeep 10+ year member]

Whats a good size for a sealed enclosure? 2 cubic feet for both? How much louder would a ported enclosure be? Louder than the bandpass i have now or would it just hit alot cleaner and hit highs and lows better?

 

[miker 5,000+ posts]

like the guy said above.. 2.4cf for two of them sealed. I reccomend doing this if it is your first box build, either way you will go it will sound better than your current box.

btw.. what amp did you get?

 

[xj-jeep 10+ year member]

Alright cool i have plans for a 2.58 cube sealed and after the subs are in there it should be close to 2.4. I got a Fosgate 500s amp.

 

[miker 5,000+ posts]

So it is a 2 channel amp? The other reason it may not seem loud is because you don't have everything hooked up "properly."

What are the impedance's of the subs you have?

btw everyone thought this was a good deal because you said it was a 1500... This wasn't such a great deal...

 

[xj-jeep 10+ year member]

The amp is a 2 channel. I dont know the amp is 500 rms, 1500 max power. My old amp was a cheap 550 watt max power that was probably pushing 200 rms... The impedance is 4 ohms