What the best way to hook up my nntx-2137amp to my

whats the wattage of the subwoofers and you should buy an amp even if its small to power your subs not good to run them off a regular radio and just tuck the wire underneath the trim along the sides of the doors you might have to unscrew them but its the best way

1st have your subs facing inwards towards the front of the car, not facing out the boot, This creates a better bass.

Wire 1 sub to one channel and the other sub to the other channel.

Turn down your gain as low as possible and then power everything up.

turn volume to desired loudness and then start turning up the gain slowly, if distorts a little turn in back down a notch.

avoid using bass boost, I agree it sounds great but it puts more strain on your amp and shortens its life.

after sorting out your gain, tweak all others until sound is bassy and clear with no distortion.

If you would like to use bass boost, turn on bass boost first, then up your gain etc.

if you have 1 sub u need a mono amp, two subs you can use a stereo amp on "two channel" mode if its NOT bridged, 4 chanel is more for 6x9s
this guide should help you alot :)

http://www.crutchfield.com/S-vGdyKqs7MMf/learn/learningcenter/car/subwoofers_wiring.html

Ok, your post has two different models listed. Let's start with something you need to know about your amplifier. Is it one ohm or two ohm stable. This will make a difference. Also, whether your subs are single voicecoil (HFI12s4) or dual voice coil (HDI12d4).

Let's start with the easy scenario. Let's say your amp is two ohm stable and you have two single voice coil subs. It's simple. You go from the positive of the amp to the positive of both subs and the negative of the amp to the negative of both subs. This will provide a 2 ohm load to the amplifier, thus pulling all the power out of it.

Unfortunatley, if you have two dual voice coil subs, you won't be as efficient. You will only have the options of a 4 ohm load or a 1 ohm load.

This is where having a one ohm stable amp would come in handy. If the amp is one ohm stable, hook the positive of the amp to all 4 of the positives on the subs, and hook the negative of the amp to all 4 negatives of the subs. This produces a 1 ohm load.

WARNING!! If you have a 2 ohm stable amp DO NOT use the last wiring scenario. It will fry your amp.

Now, the last is a little trickier. This is for two dual 4 ohm subs. Follow closely. Hook the positive of the amp to one of the positives of each sub. (do the next step to both subs) Go from the negative of the voice coil that you hooked positive from the amp is hooked to, and hook that to the positive of the unused voice coil. Then go from the negative of that voice coil and hook to the negative of the amp. Make sure this is done on both subs. This will give you a 4 ohm load.

Hope this helps

If the amp is a 2 channel I would hook up each voice coil to a different channel. Also, make sure you hook your amp up as close to the sub as possible. With a sub that size you need to eliminate any delay in signal transfer because the sub is so larg.

Well i tried looking up that amp, but Fosgate sight is down. So assuming that the best power out of your amp is 2ohms off the bridged hookup, and the subs are 4 ohms per coil, the best way is to only use one side of each speaker and hook it straight the the bridge. Only using one hook up wont hurt anything, its just for giving you wiring options. And when adding up ohms of speakers, it goes like this. If you had two 4 ohm subs, that'll give you a 2 ohm load. If you hooked up all your hookups, it would be like having four 4 ohm subs, and would give you a 1 ohm load.

Yes you can use the pre out to hook up an amp and subs. Probably the best way to send the signal to an amp to run the subs.

Try this wire diagram for speaker connection

Connect one to each channel, for the best sound.

front right and left connect to 'a' speakers out. rears to surround output. sub only to the preout