Ways to Keep Rockford amp from shutting off...please read!


Hi, i know there have been many posts about this but I cannot find any answers...please help!
I have a Rockford Fosgate 1500BD amp powering two 12" Kicker Solobaric L7's, each have 750 RMS, and my subs give each full power by pushing up to 1500 watts RMS...My question is this. My amp shuts off after i crank the bass up, and i want it so it doesnt. I have a new 200 AMP alternator coming my way, to replace my crappy 75 amp one. I wired hte ground and power correctly, with 4-gauge wire, my question is how should i wire the subs to the amp? I have it bridged now i believe, i have the 2 +'s connected to the + on the amp, and the 2 -'s connected to the - on the amp. I'm not sure what the whole OHM thing is, and i think its supposed to be 2 OHM or something? If somebody could look this up, and tell me how to do this correctly i'd really love it! I have a 1 farad legacy capacitor sitting in my garage too, im not quite sure on how to go about hooking that up to, if that will even help. I'm hoping with a new alternator, and possibly that capacitor, and a new way of running wires to the subs it wont shut off. Please help!!! Thanks! my AIM screen name is JuViFaN1 and thats also my email address at @aol.com. Thanks...please reply ASAP! I APPRECIATE IT GUYS! THANKS!!!
-Tim Sylvestre

Hey tim,the lowest load the 1500bd is designed for is 2 ohms.Now L7's come in dual 4 and dual 2 ohm coils.I dont know wich ones you have but either way from what you described both subs with paralleled voice coils and then paralleled to the amp mean big trouble.If they are dual 4's that gives you a 1 ohm load on the amp and if they are dual 2's that gives you a 1/2 ohm load......BIG TROUBLE!!!!!!!!.Now,if they are dual 4's there is no good solution because with both subs connected the lowest loads you can get are 4 and 1.A 4 ohm load wont make much power on that amp and 1 is too low.BUT,if you are lucky enough to have the dual 2 ohmers its an easy fix.Connect the voice coils in series by putting the + of one coil to the - of the other coil.Do this on both subs then connect them in PARALLEL on the amp.This will give you a 2 ohm load,just like your amp needs.An easy solution to a big problem.Good luck!!!!

Hey, thanks alot...here are the specs...
titanium deposit cone
non-resonant aluminum basket
Santoprene rubber surround
dual 2-ohm voice coils for wiring
flexibility (with a compatible amp)
frequency response 20-100 Hz
power range 75-750 watts RMS (375 watts per coil)
peak power handling 1,500 watts
sensitivity 86.6 dB SPL
top-mount depth 6-13/16"
sealed box volume 0.88-2.0 cubic feet
ported box volume 1.75-3.25 cubic feet

Good or Bad???? LOL...pleaseeeee help! and so i can fix that by what u said by connecting the them in series...i still dont get it...the amp has two things for speaker input...its got ONE + slot, and ONE - slot....
I've got two terminals on the box, two sets of +/- wires...which of these do i connect, then on the amp? I'm still kind of confused about the whole parallel thing...sorry im dumb lol

Inside the box on the back of the subs there were 4 connectors for hte wires....one was solid black, one was solid red, the other two were red with a dot, and black with a dot.
I put the wires to the solid red/black on each sub.

So i had four wires coming out of the box to the terminals...I dunno if that helped...

OK........here we go.You have the dual 2 ohm subs,thats a good start.On the back of the subs connect BOTH red terminals and BOTH black terminal together.You can either run 2 small wires from one set too the other and then run another set of wires to the connectors on the box,or you can run a set of wire from both sets of terminals to the connector on the box.That will but Both 2 ohm coils on the sub in parallel making it a 1 ohm load.After both subs have their coils in parallel connect 1 of the - terminals on the back of the box to the + terminal on the other side with a piece of wire.This takes both 1 ohm loads and puts them in series making the whole thing one 2ohm load.Now put the remaining + from the one side and the - from the other side to the connectors on the amp.Confused?If you cant figure out my post click on my name and drop me an email with your number and i'll call you and walk you through it.

that is a brilliant solution MEXXX you know your stuff.

Meex, thanks again...heres another situation I've encountered.

I rewired hte subs to 2 - OHM, and im sure i did this right, as i based it off a web diagram from the amp booklet. And its just like you said. Anyhow, the subs were hitting and not shutting off! I was like yesssssssss until after about 15 min with them reasonably loud, the amp shut off again. I figured it was good because atleast it played for 20 min loud as hell. So i shut down my deck, powered it back on, and to my satisfaction the amp turned on. However this time, it shuts off when the volume isnt even loud. What should I have the settings on the amp set to? Could that be the problem? Does it need a big rest to cool down after about 20 min of it being pretty loud? I've parked the car for the night since i am at college. What could the problem be? I hope i didnt blow the amp, but i figured if i did hten it wouldnt even turn on. So basically...if its hte settings (because i adjusted them) what should they be set to? something is like "gaine" and the other is frequency or something?

Let me know
thanks man
-Tim Sylvestre

If you managed to get the correct load there is only 2 others things I can think it would be.Either the voltage is dropping enough to cause the amp to shut off or you are playing the amp into clipping and it doesn't like it.Do you have or know someone that has a multi-meter?If you can get one,then set it on dc volts and put the probes somewhere close to where the power wires go into the amp.Check the voltage when the bass hits at a sound level close to where it shuts off.If it drops to 11 volts or under than that is a problem.You said you are getting a new alt which will really help but I also suggest investing in at least a 1 farad cap.You can pick one up on ebay for around 50 bucks.Dont be concerned about the brand of the cap or if it has a digital top,99% of caps are the same and its not worth paying more for one with a familiar name brand sticker on it.Oh,if you do find a meter check the speaker wires that go into the amp to see what the impedance is.One last thing,for a clue to tell if you are playing the amp into clipping or not,when you turn the volume up to its loudest setting normally there will be a spot where the volume control will go higher up but the subs dont seem to get any louder.DO NOT play the amp after that spot,this is when amps start to clip.Any other questions you know where im at.......lol.

P.S.- If do have a chance to check the voltage do it when you first turn the stereo on and after you have played it long enough for the amp to start shutting off.Your alternator may not be able to keep up with the load leaving the amp to drain your battery below the amps cut off voltage.Also,dont be too worried about blowin the amp,those things are pretty well built.

So the subs are not going to blow? I really hope not, they are fairly new. So with the new alternator (that im installing this weekend), and I got a 1 farad legacy cap too...so with those two things added...I shouldnt have a problem? and if i still do, whats wrong then? Am i ^$@^@d?? haha...thanks man i really appreciate it!!!!!!

The only way you can hurt those subs with that amp is if you play it into distortion causing DC clipping.Be sure to let us now how the new alt and cap turn out.Good luck!!!!!

Hello, i now believe somethng is wrong with one of the subs. I tried hooking one sub at a time up the amp, and one sub works fine, never shuts off, when wired in parallel. One works fine, never shuts off, will hit as hard as it can for ever...the other however, when hooked up the SAME way it shuts off after about 10 seconds. What can I do? Whats the diagnoistic? Do i have to return it? The thing is i bought it off ebay, it says it has a warranty on it, but thats a pain in the BUTT. Anything i can do? Anything you suggest i try?

-Tim Sylvestre

Hmmmmmmm.......before it shuts of does it make any staticy sounds or anything?Try taking the sub that makes the amp turn off and connect one voice coil at a time.Dont turn it up to loud though,you might burn the coil out because at full volume 1500 watts will be goin to it.If one coil makes it shut of and the other doesnt than that would lead me to believe that it is the sub.

tim sylvestre
do you mean just connect one positive one negative and make a wire go from that to the amp? dont parallel it or nething?

yup,just connect one set of + and - at a time to see if one or the other makes the amp shut off.

good news, well maybe bad.
The new alternator is in! but anyway...
when i connected the - to the BLACK WITH DOT on the sub, and hte + to the RED WITH DOT on the sub, it worked. The amp never shut off, and the sub hit as hard as it could.

So..am i screwed? Or is there a way to wire it to 2 OHM with only those two terminals working?

Let me know ASAP
thanks guys

Did you try connecting just the + and - without the dots?And to answer your question,no not really.I do not suggest only connecting one coil from each sub.If there is something wrong with it,it would be better to just replace it.

Tim Sylvestre
i know it'd be better to replace it, but I'm not gonna throw $250 out the window that it cost for each sub. There is no possibly way of hooking it all up in the right way sacrificing that one of the subs cant be hooked up in parallel or series or w/e? Theres no way? I'm willing to sacrifice sound for it to work....like since the min. is 2OHM what if i wired it to 4OHm or is that impossible?? AHHHH im pissed off and stressed

Like I said,I dont really suggest it,but if you absolutely have too..........take one coil from each sub and connect the two in series.Thats really your only other option if the sub is really damaged.Did you try connecting the other coil to see if thats really the problem?

yeah thats the problem...i think im just going to say screw the system anyway...so if u know any1 who wants to buy 1 12" L7 or a rockford 1500BD amp let me know...thanks

hey i have a question...i hope someone can help me...i have two 12" Rockford HX2 RDF2212 Subs. and im thinking about buying a Rockford 1500bd Amplifier...but i dont understand this OHM thing im hearing...the subs i got are dual 4 OHM Voice Coils..so i duno...MEXXX said dat's not a good thing...so i duno if i should buy the amp...can someone email me at infamouschi1214@hotmail.com or post a message to let me know if i should buy it..thanx alot

Thats not a good thing those subs can handle 500 a piece so thats 1000 watts and that amp can deliever 1500x1 @ 2 ohms and 750x1 @ 4 ohms u will either underpower those subs or overpower them

Its not that 1500 watts is to much for 2 of those subs, its just a bad combo for that amp. You cant get a single 2 ohm load using both subs.
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