I have two 12" Rockford Fosgate HE's (4 ohm) and a Rockford Fosgate 500bd amp (not recommended for impedence loads of less than 2 ohms) that was rated an actual total power of 638 at 2ohms. I was wondering how i should wire these, and also any other suggestions for getting the best sound out of it. Thanks!!

its easy. just wire the positive (+) of one sub to the posititive of the other sub to the positive terminal of the amp. do the same for the negatives. this will present a 2 ohm mono load to the amp. im not sure about the particular model you have, but if it is a two channel version, just wire it in "mono" or "briged" mode according to the manual, so that you only have on of each: positive and negative terminals.

afer that, turn the gain knob and crossover knob (assuming you dont have an external crossover) to thier lowest settings. put in a a very bass-heavy cd (dj magic mike, mystikal, etc.) and turn up the headunit volume about 2/3 of the way up. turn up the gain knob on the amp until you match the highs or you begain to hear clipping (you probably wont hear it though, just turn it up till it sounds good).then experiment with all kinds of material to set the crossover knob. depending on what kind of music you listen to and what effect you are after, this will probably be from about 60hz to 150hz.

BTW..im typing on my girlfriends keyboard, so there will be lots of typos. sorry! ;)

But if they are already mounted into the box, how would i mount the (+) of one sub to the (+) of the other. I put them in the box not thinking so i just hooked the subs to the terminals on the back of the box. So i have this setup: I mounted the two subs into the box with the power on the sub running to the power of the terminal on the back of the box and the negative on the other sub running to the negative of the terminal on the back of the box. So all i have to deal with now are the two terminals on the back of the box(both with a positive and negative connector), there are two. How would i do the above wiring with that w/o taking the subs out of the box again?

im assuming that when you use the word "power" you mean "positive" (not really important, just helps to clarify ;). because the subs run off of an alternating current circuit, the "power" is being switched constantly; the speed of which is determined by what frequency is being delivered to the speaker). it sounds like all you have to do now is wire the amp correctly to to box, it sounds like the subs are pre-wired in the right way. just make sure all the positives "touch" so to speak, and all the negatives are the same.

So i should be alright running |AMP|---(+)--->|SUB1(+)|---(+)---|SUB2(+)|? Same with the negatives. Just think of me having two seperate boxes and trying to wire them to the same amp. The type of terminals are binding posts. Thats what confused me a little, cause if they were just wires it would be easy to go like that, but since they plug how am i going to connect the (+) of sub1 to the (+) of sub two if im already plugged into the back of sub1 from the amp. I really hope you can vision this cause this sounds confusing. Thank you so much for all the help so far too!

if you think of them as in two seperate boxes, you could run it in one of two ways:

1) from positive post of sub on to positive post of sub two to the positive termianl of the amp.

2) the porsitive terminal of sub one o the positive terminal of the amp, and the positive terminal of sub two to the positive terminal of the amp.

in the first instance, you would have two wires connected to the terminal of sub two, and in the second example, you would have two wires connected to the positive terminal on the amp. assume in both instances the negatives work the same way.

if the box has only one terminal (with one each: + and -), then its pretty safe to assume that inside the box the +s and -s are already connected together, so you can simply connect the amp in briged (or mono) mode to the box as if it were one speaker.



edit: forgot to add..in th eabove example you are absolutly correct. you can think of it just like that. :thumbsup

By wiring like said above (parallel) you are coming out to a 2ohm MONO load which means that your amp must be able to handle a 1ohm load. When an amp states that it is 2ohm stable that means 2ohms stereo which equals 4ohms MONO. If you wire like said above you will blow up your amp. You would have to run them 4ohm stereo. Either that or trade in your subs for some 2ohm or 8ohm versions. See link for further explanation.
http://forums.2gnt.com/dcforum/DCForumID18/924.html

Wait a minute, now im going to blow my amp because i ran them parallel??? Who am i supposed to believe here and what should i do. I wired them in parallel and they sounded good. I dont know what to do, now im really confused!!

jerseystyle did have a good point, but upon reaserching the amp i found that it is safe to run it in 2ohms mono, so you can wire it like ive said above. most of the time when an amp is rated as safe when seeing "X ohms", it referes to the stereo rating (X ohms per channel, and 2 times X ohms in mono), however because you have a one channel amp, the 2 ohm rating applies to just that channel. you wont blow anything up. ;)

Right on, thanks for doing research for me, stars for you!