you have two differant subs in one system? *doh*

But, if they are dimming at idle, I'm guessing you got a cheap aftermarket alternator. It is probably 130amps at high RPMs, but like 30 amps at idle. It's gay I know, but manufacturers do it.

The horror that is the ohm load going to your amp makes me wonder why it hasn't blown up yet, but what the hell

 

yea *doh* is exactly what im thinking, i only have 2 differnet subs because the matching one i had blew, and i had an old MTX laying around in my house that blew and i remember that i got the protection plan at Circuit City so i got a new sub for free. ever sense i've been in kinda finacial trouble so replacing them has been at the bottom of the list..

now that alternator yea your right its low at idle but not 30 amps...company proclaims to rate tha alternator at 60-70 amps at idle and 130-135 amps at 1500-1600 rpms

 

How much power are you running?.. saying 65 amps, at idle, and 14 volts, on the low end, you should easily be able to hadel 900 watts without any problems.

What kind of battery do you have? They should last more than two years but if you really abuse them, they can go bad.

In your case a cap might actually be the only option left, I'd suggest something in the 5-10 farad range. Another solution would be take out a sub, sounds like you're running a 1 ohm load which makes the amp very power hungry. Or, wire the subs up differently to yield a higher impedance. There's a whole sticky at the top of this section with wiring diagrams to help you out.

 

Well amg, the problem is here, The roadthunder is 4ohm, and the other sub is 2ohm. That amp he is using is probably only 4ohm stable bridged. His setup is screwed 5 ways till Sunday

 

WTF? A 2 and a 4 ohm sub in the same setup? With a 4 ohm stable bridged amp? Ugh. Well, I'm assuming that someone who knew what they were doing hooked it up? So you had two 2 ohm subs and a 4 ohm stable amp. That means that you're prbably wired in series. (two 2 ohms subs in series = 4 ohms)

So with the 2 and the 4 ohms sub you'd be running 6 ohms and you're fine. Just get a new audiobahn and hook it up and you'll be back to normal.

If they're wire in parallel you're in some trouble. That'd be 1.714 ohms. Take out the audiobahn and just run the road thunder unitl you can get another audiobahn and wire them in series.

 

alright here's the run down.

at first i had two Audiobahn AW1251T

Peak- 400 RMS at 2 OHM
Dual 4 Ohm
2 or 8 Ohm Operation

than one blew.. so i just went up to circuit city and did my little replacement thing they offer that i had on a mtx i blew some years back.

12' mtx roadthunder
single voice coil 400 rms at 4 ohms

now for the amp....

-audiobahn A4002T
Common features
Class D Power Amplifier
2 Ohm Stable
RCA (Low Level) and Speaker (High Level) Inputs
RCA Outputs
Mono Output
Input Sensitivity: 200mV ~ 8V
THD: <0.05%
Variable Low-Pass Filter: 40Hz ~ 120Hz
Variable Bass Boost Control @ 45Hz: 0 ~ 18dB
Air Induction Fan Cooled
Optional Accessories: ABR100T (Remote Mount Bass Boost Control ****)
ADM100T (Remote Mount Digital Volt Meter)
4-Way Protection Circuitry: Thermal, Short Circuit, Overload, DC Offset

-4 ohm stereo ~~100x2
-2 ohm stereo ~~200x2
-4 ohm mono ~~400x1(bridged)
-2 ohm mono N/A

 

It's 2ohm stable in stereo mode, but if you bridge it it has to be 4ohm. Just the evilness of running that Roadthunder and an A-bahn in the same setup is too absurd for words.

 

ok well i dunno who started saying that i have it bridged.
the road thunder is wired normal and im a noob at the names but its + to + and - to -

the audobahn sub on the other hand im not so sure of off the top of my head due to it having dual voice coils and i guess you would cauuse it 4 different set of posts but 2 pairs on each side.

if i were to bridge the audiobahn, it would fail to work, because the sub is only suppose to run at either 2 or 8 ohm not 4.

edit: the audiobahn is wiried in parallel
here is the link provided by audiobahn for dual lug subs.
single sub.

http://www.audiobahn.com/tech/wiring...sub_wiring.pdf

 

I'm completely lost. Sounds to me like you got pretty well screwed when you bought all that audiobahn stuff if the impedences don't match up. My suggestion is to wire the audiobahn sub's voice coils in parallel and hook it up to the amp. Use the MTX as a candy bowl or something.