What am I missing for my sub/amp installation


CarAudio.com Newbie
Hello everyone, I am pretty new to installing subs and amps so Im looking to make sure I am going in the right direction and am not forgetting anything I need.
This set up is going into my 1992 civic vx(EG hatch), I have a JL 13W3v3 4ohm 600 watt subwoofer and a stage 2 box for it both linked down below. i also have am buying either an 800 (200RMSx2) or 600 (150RMSx2) watt amp tomorrow from Rockford Fosgate (linked below as well) From my research and what my friends tell me an amp with higher watts is ok to run with a smaller woofer as long as you dont turn it up all the way because thats where damage can happen. Is this true or sound a amp with the same watts as the sub just always be better?
So now that I have those from my knowledge all I would need is a wiring harness for my stereo, RCA wires that run from the stock stereo harness to the amp, power wire/cable for the battery to the amp as well as a ground wire also. Speaker wire for wiring the sub to the amp and Id need speed wire to run from the amp back to the stereos after market harness. Im sure I will need to upgrade my alternator and get a larger battery, would I need to upgrade any wires under the hood as well?
Thank you to everyone who's taken the time to read this and can confirm that I am getting everything I need and/or help me out in any way.
Also I plan on doing a very quality job and only want to buy quality parts, if anyone has suggestions on what brands to get for the rest of the things I have listed or what gauge wire ill need that'd be super appreciated.

2023 LTZ

CarAudio.com Regular
I think having an amp 10% on either side of the rms sub wattage is ideal. Opinions vary, some may say go double the sub wattage to have overhead or room to upgrade if chosen down the rd. Be sure the amp can handle the ohm load of your sub. Why don’t you get a mono amp that’s 600-1000w? Rockford has a reasonably priced 750w. $349
I can’t offer any advice on wire harnesses.
You’ll need a power wire from battery to the amp. A fuse about 12”-18” after battery, weather resistant is good. If the amp requires 4ga you have a choice to run that size all the way or run larger then reduce down near the amp. Always use the same size power and ground. A solid ground in the back that’s directly to a chassis location.
Rca or signal wires to feed the amp, your remote turn on, as you mentioned.

the big 3 is almost a necessity in audio upgrades. Alternator, battery can come later if needed.


Senior VIP Member
10+ year member
You will be using roughly 80amp and going only 10 or so ft so you could use as small as 8ga. If you think you might upgrade later and use mor or bigger amps then get 4ga now and you’ll be good. I would research “big 3 upgrade” it’s very simple and you can use your 4 ga wire or get some battery cables from the parts store. Alternator and battery will just depend on what you have in the car now, it may be enough to keep up. And you will need a fuse close to your battery on your power wire.
As for getting a bigger amp and not turning it up is fine. Watch some YouTube videos on setting amp gains.


CarAudio.com Newbie
I dont plan on upgrading more in the future I already know Ill be more than happy with this. Unless there is any harm that can be done I think ill go with 4 guage wire since it can handle roughly 815 watts RMS. I plan on having the amp mounted the the back of the rear seat next to the sub so I should only need 11-14 feet to be safe.(car is 13.5 feet in total and battery is located in back of the engine bay) On the honda forms everyone is telling me for that amount of power the stock battery and alternator will be just fine, one of the guys said he was running twice the power on the factory battery size and factory alternator, so I dont think ill need to upgrade those atm. For a fuse should I get an ANL or ANG fuse? the one im thinking about is listed below it is for 4 - 8 gauge wire. Also I assume the closer the fuse is to the battery the better? And I assume I should get an 80 watt fuse, but would a 60 watt protect it better but it would burn out without being turned up as high?
I havent checked out mono amps and dont understand how they are different, I was just planning on going with a 2 channel amp but is there any pros for the mono?

https://www.crutchfield.com/p_142DFB0/EFX-DFB0-Delta-Dual-Fuse-Block.html?tp=70106 - Fuse box
https://www.crutchfield.com/p_007CPC217/Crutchfield-2-Channel-RCA-Patch-Cables-17-foot.html - RCA wires
https://www.crutchfield.com/p_007CPWB4/Crutchfield-Black-Ground-Wire-4-gauge.html - Ground wire
https://www.crutchfield.com/p_120MANL80/T-SPEC-V8-Mini-ANL-Fuses-80-amp.html?tp=70082 - Fuse

Also forgot to link the sub and box I am using as well as the amps I am choosing between: https://www.crutchfield.com/p_575T400X2A/Rockford-Fosgate-Power-T400X2ad.html - Amp
https://www.crutchfield.com/p_142HA02B/Scosche-HA02B-Receiver-Wiring-Harness.html - Wiring harness
https://www.jlaudio.com/collections...ucts/13w3v3-4-car-audio-w3v3-subwoofers-92157 - Subwoofer


Senior VIP Member
10+ year member

Would this be fine and have everything I need?

Also how do you figure out which LOC to get? Should I get a 2 channel one that has a 800 watt rms since thats what my amp is?
You need rca for both Amps.
Sounds like you've done your research, and have a pretty good idea of what you need to do. Kudos, most people don't make the effort.

A 2ch amp would work, but a mono one ch amp is going to be built better for larger power. A mono amp can only run in mono. A 2ch amp can run in stereo, its not something you need for subs. (If you are old enough to know black and white tvs, then around that time they had mono or stereo settings). If you think of it like surround sound on a tv, its basically adding left and right (stereo) vs adding a front center (mono).

That single voice coil sub is kind of throwing a small monkey wrench into it. Keep in mind that is also a single voice coil 4 ohm sub. That is something that would usually be wired up with at least a second sub so it can be wired down to 2 ohms. You can obviously find an amp, but you are going to be limited. 400w will work, but if you are here right now, you could do as high 550w comfortably if you can find one @4ohm.

Your power wire that comes off the battery for the subs should be fused as close as possible to the battery. 12-18" is the max, but you want it as close as possible, and you can find fused battery terminals. The point of that fuse is, is to fuse the cable. If you do it 18" after the battery then you have 18" of cable that is not protected. As far as the fuse, your amp should have it's own fuse on the amp. If the amp says it can do 75amp fuses, then fuse the cable at 1 or 2 steps higher. Unless you dial in and know exactly what its pushing fuse the cable about 15% higher (as long as the cable is rated for it, ex. for 75 amp I would fuse the cable at 100amps).

The fuses are just style preference. For that wattage, it's pretty much which ever you want.

That Pa4bx kit, has everything to get the amp powered. You would just need speaker wire.

If you have a 400watt amp, its going to be usually 80-90% efficient, (meaning if its putting out 400 watts, at 80% efficient its drawing and using 500watts. 400w /.80 = 500. They are generally about 85% efficient which is 470 watts. 470 / 14.4v = 32 amps being drawn by that 400 watt amp. Amps aren't going to be exact either. That RF is probably pretty close, but you have to give it a little room if you aren't using a multimeter and dialing it in exact. Not sure about your Honda, but in general I'm thinking they have smaller electrical setups, especially one from 92, but I'm sure yours isn't original any more. Basically, if you get this all hooked up, do the big 3 wiring off the battery, and then your headlights dim on bass hits, then your battery is not able to keep up with the draw. If you run it at high for hours and after some time your voltage starts dropping, then your alternator can't keep up. I would definitely do what you have planned first and see how its working before upgrading electrical. Many vehicles wouldn't need to upgrade for that.

I know you probably don't want to hear it, but back to that sub being 4 ohms. You could buy that same sub in a 2 ohm for the same price as that amp. You could then sell that sub you have, (probably pretty quick), and get an amp that will run at 2ohms. That way you would at least be able to still use same enclosure. You might be able to find the 2 ohm sub on ebay or around the boards for about half too. If you can find an amp that pushes out more than 500w RMS AT 4 OHMS, then you can always dial it down. The 400w amp will work, but at the very least, I promise you this is the time to think about it before you buy the amp. Figure out the cost, and I would bet anything if you sell your amp, you can get a better amp for that sub and all in be about the same. Not the most fun choice, but ....

Otherwise if you like RF amps, why is the T750X1BD not the amp you're going with? I've had one of these style amps. They have their own clip indicator light so you can properly set the gain without any other tools.
Power 750 Watt Class-bd Mono Amplifier| Rockford Fosgate ® (crutchfield is backordered)
Rockford Fosgate T750X1BD Monoblock 750 Watts RMS Class BD Power Series Ultra Compact Motorcycle Amplifier (woofersetc.com)

If you're still looking for amps, look for the companies that make SMART amps. JL audio and taramps are two that I know of. They will push the same wattage at different ohm ratings, and probably your best chance to expand your search.
Last edited:
  • Like
Reactions: 2023 LTZ

About this thread

Who Replied
Last reply date
Last reply from

Latest threads

Latest posts