I got a 12" infinity 1242w and I'm not sure about it's install. It has 2 sets of +/- plugs (on opposite sides of the sub), which I've never dealt with before. I hooked it up yesterday and my amp kicked off (went into protect mode). anyone know how to install this?

8/31/2007 4:48:48 PM

those are voice coils, each has the same impedance you need to figure out at what ohm load your amp will deliver the most power and still work (for ex mine will go as low as 2/3 of an ohm)

if your amp is class a/b and is a 2 channel you can wire each channel to a coil, if it's a class d or mono amp you will need to wire in series or parallel based on what ohm load you want

parallel will lower your impedance for example 2 4 ohm speakers wired in parallel will present a load of 2 ohms to the amp

series will raise your impedance, so those same 2 speakers wired in series will present an 8 ohm load

here's a good link

http://caraudio.biggz.com/parallelseries.html

hit me up if you have more questions

8/31/2007 6:27:05 PM

thanks bud. to be honest, you're well beyond my knowledge of this stuff. I've got a 400 watt 4 channel jensen amp, with 2 6x9's on it right now (they're not bridged). i guess my first question should be is my amp good enough to run all of this?

8/31/2007 6:29:52 PM

what's the model #?

what you're gonna want is either 2 amps (which will drain your battery quick fast and in a hurry) or a 5 channel amp with the 5th channel being more than any of the other 4 (made for a subwoofer).

8/31/2007 6:35:44 PM

the amps model # is LXA400 and it's pretty old

just to let you know, i'm not really looking for anything spectacular or too loud. i have a pretty shitty set-up since i don't have much money. that being said, do you think there's a way to do it with the amp i have?

as for how i have everything set-up, I have a stock HU, stock speaker wires, spliced off the two rear channels to my line level converter, then just RCAs to the amp, then the 6x9's. i basically did this because i had everything to do it, and my stock system is horrible. i really just want to be able to hear my radio (i could barely hear it when i was on the highway with the windows down), so i put these speakers in. and i got this sub for a deal, so i was hoping i could just throw it in as well.

8/31/2007 6:45:05 PM

the only way to do that would be to bridge the other 2 channels and wire the coils in parallel

you're still going to be underpowering the subs, but it should be ok

just make sure to not treat the gains like a volume knob

8/31/2007 7:36:41 PM

i've tried all the wiring options i've seen, but my amp is still getting kicked off. i've also tried not bridging it, and switching around what channels i bridged

i tried these two wiring options:
http://www.rockfordfosgate.com/rftech/woofer_wizard.asp?submitted=true&woofer_qty=1&woofer_imp=4

i have one 12" dual coil @ 4 ohms sub and a 4 channel 400 amp, rated for 2,4, and 8 ohm speakers

anyone know anything else to do? and i don't know a lot about all of this stuff, so talk to me in n00b terms.

9/7/2007 5:12:45 PM

Take your amp, take 2 of the channels and drive your 6x9s. Take the other 2 channels, take the + from the left channel and the - of the right channel to the sub....take the + you just got and attach it to ONE + on the sub. That + will have a - with it. Take that - and attach a wire from it to the other + on your sub. Then take the - from the amp and connect it to the leftover - on your sub. So you'll have +- from the amp attached to the + of one voice coil and the negative of another voice coil. Then a single wire from + of one voice coil to - of the other voice coil, wiring your coils in series for an 8 ohm load presented to your amp.

The amp should stop going into protection.

Quote :

"the only way to do that would be to bridge the other 2 channels and wire the coils in parallel you're still going to be underpowering the subs, but it should be ok"

No, he doesn't want to put a 2 ohm load onto a bridged amp that is only stable at 2 ohm stereo.

9/7/2007 9:05:54 PM

chance, i've tried that before. that way works until i turn up the volume, gain, or turn on the bass boost. it only works at levels were you can't even hear the sub. any other ideas?

9/9/2007 5:11:15 PM

ttt!

9/10/2007 4:50:23 PM

Dunno without having my hands on it all myself. Try taking the 6x9s off the amp and putting the sub on these bridged channels. You could also try hooking up one stereo channel to one voice coil (ie +- from the left speaker on the amp to +- on one side of the sub, and +- from the right to the other side/coil of the sub) and see how that works.

Do you know how to properly set the gains on the amp? What is the range of volume on your headunit and how high do you take it? That is, does your amp go from 1->25 or perhaps -70->0 or something? And where is it set when you have it at your max listening volume?

I google your amp model number and it seems to be bridgeable, but if it is an older model of the same number, perhaps it isn't.

9/10/2007 9:57:12 PM

yeh, i've taken off the 6x9's and tried it. i also tried hooking up a channel to each coil. neither worked. i normally listen to the stereo all the way up since it's so quiet, but i've had it turned down way low trying to get this sub to work. as for the amp, the gain level just says min and max. the lpf and hpf go from 40 to 240. i've tried playing with all this (going from all the way down, then going up slightly, etc) but nothing worked. i know the amp is bridgeable, it even says it right on the amp. i've tried bridging my 6x9's but it makes the amp run extremely hot, so I put an end to that, but I figured that the sub would pull enough power from the amp that it wouldn't overheat.

i may try to see if an car audio shop will hook up my sub to something to make sure that the sub isn't the actual problem. and if they can get my shit to work, then i'll repay them by buying a box for it.

thanks chance

9/11/2007 12:36:09 AM

I meant what is the range of your stereo volume control? And how did you bridge your 6x9s, you hooked 1 speaker to 1 bridged pair and 1 to the other?

It doesn't make sense to me that your 6x9s work and your sub doesn't....unless there is something wrong with your sub or you are hooking it up wrong?

9/11/2007 8:58:20 AM

yeh, i'm not sure of the volume range on the HU. it's stock and just has bars indicating the volume level, with no numbers. as for the bridging, I did one speaker on A+/B- and the other on C+/D- i tried briding them as A-/B+ and A+/B- but the speaker hooked up to A-/B+ didn't work. is there something wrong in doing it that way?

i'm guessing there must be something wrong with the sub, because i've tried wiring it so many ways and nothing worked. i'm gonna run by an audio shop and see if they can get it to work. thanks chance, you've been a really good help.

9/11/2007 9:54:30 AM