Skip Navigation

Connecting your car speakers to an amp

Tip: You can use your vehicle's factory wiring

Buck Pomerantz was born and raised in Philadelphia. His parents bought their first television set when he was born. He figured out how to run it by the time he was two. Besides athletics, his formative interests included electronics, amateur radio, music, and stage crew work. He got his BA in writing from Brown University. Then he joined a rock 'n roll band as their soundman and moved to Charlottesville, Virginia. After that venture failed, he spent time in Boston, New Orleans, and Berkeley. He worked in a music store in Austin manufacturing, installing, repairing, and operating sound systems for recording studios, clubs, and bands. He moved back to Charlottesville, ran a little recording studio and finally joined Crutchfield as a copywriter. He has 2 grown children and 3 grandchildren, but after a good nap he can still rock out.

More from Buck Pomerantz

Installing an amplifier

Sending the audio signal from a receiver to a 4-channel amplifier's inputs via RCA cables or the amp's speaker-level inputs is straight forward and simple enough, but getting the amplified signal back to the speakers—well that's another matter.

Getting signal to the speakers

The speakers are usually in four different corners of your vehicle, and running separate new speaker wires to each one presents many challenges, including how to get the wire past the car door hinges to the front door speaker locations.

A convenient way to send the powered signal from your amplifier to your speakers is to run the speaker wires back to the harness behind your stereo, where all your car’s speaker connections are accessible in one place.

Which speaker wires go where?

Normally, when you install a new stereo, all the wires from the stereo would connect to the car wiring adapter. The wires would run from one black connector to the other (the right side of the photo below).

But since we're using an external amplifier for the speakers, the speaker wires from the car get diverted to the amp — that's the bundle of wires on the bottom plug heading left to the amplifier.

The speaker wires from the new stereo aren't used. You can either cut them off (like we did in the photo below) or just tape them up – each wire individually – so that none of the wire ends can touch anything else.

Meanwhile, the RCA cables carry the audio signal to the amplifier and the blue wire from the stereo turns on the amp whenever the stereo is turned on. And yes, fade and balance controls will still work fine, so long as you connect the RCA cables correctly.

StreetWires iCS920C multi-conductor cable

New speaker wires from the amp connect to the speaker wires in the stereo adapter harness

Running the amp's output wires to the wires on the adapter harness is how you avoid having to run new speaker wiring throughout the car. That's the bottom side of the triangle in the photo — speaker wires from the amp connect to the speaker wires on the adapter harness. Then that harness plugs into your car.

For 4-speaker systems, you'd need to make eight connections — a positive and negative wire for each speaker. This means, you just need to run the eight speaker wires from the dash to the amplifier, just like you do the RCA cables. In fact, when you're installing the amp, it's smart to run the RCA cables and new speaker wires at the same time.

EFX 9-wire Ultra Flex speaker wire

EFX 9-wire Ultra Flex speaker wire

Some products to help you do it

Crutchfield offers a 12-foot and a 20-foot 9-wire cable that helps simplify running eight speaker wires plus a remote turn-on lead from your amplifier to the rear of your receiver. We also carry a small selection of highly conductive, pure copper speaker wire, available by the foot, that will also work well, if you don't want the 9-wire, all-in-solution used above.

A multi-pack of Posi-Products Car Stereo Connectors could come in handy here, so you can make all the speaker connections without having to solder anything.

High-power amps need bigger wires

For amplifiers with more than 75 watts RMS of output per channel, it may be better to go ahead and run new 14- or 16-gauge speaker wires directly from the amp to each speaker.

Factory speaker wires are very thin, with high electrical resistance, so they can cause noticeable power loss when higher wattages try to get through. But amplifiers of 75-watts or less aren't really affected by this, so running their outputs through factory wiring remains a practical and convenient solution.

Let us know what you need

This article focused on a way to simplify the speaker connections. For information about other aspects of amplifier installation, like power and ground wiring, check out our Amplifier Installation Guide.

If you have any questions about connecting a new amplifier to your speakers, contact our advisors via chat or phone. They'll take the time to answer your questions and explain the details, then get you set up with whatever you need. 

  • Jason from California

    Posted on 5/24/2015 3:22:00 PM

    I don't understand. If you connect the speaker wires to the amp, then they are no longer connected to your can your speakers operate after you do that?

  • Buck Pomerantz from Crutchfield

    Posted on 5/24/2015 4:43:25 PM

    Jason, As we tried to show in the illustration, the signal comes from the amplifier's outputs. The other ends of these wires connect to the vehicle's harness. That plugs into the car, which has all the wiring that connects to the speakers. The illustration doesn't show the receiver's harness, where power connections to the aftermarket receiver are made, nor the RCA patch cables, which connect the receiver's outputs to the amplifier's inputs. Sorry if that's unclear.

  • gleidston from framingham

    Posted on 6/2/2015 6:36:45 PM

    what wires do l need to conected my pionner amp to my 2009 f 150 speakes l alredy have 1 amp to my subwoofer ,now i need to conecter another amp to my speakers

  • Buck Pomerantz from Crutchfield

    Posted on 6/3/2015 9:59:23 AM

    Gleidston, This article spotlights a method of connecting an amplifier to speakers using a multi-connector cable like EFX's 9-conductor cable. You would use RCA cables for the amp's input. If you buy your wires from Crutchfield, you could call Tech Support for free help wiring your system. Their toll-free number will be on your invoice. If you purchase your equipment elsewhere, you can still get expert Crutchfield Tech Support - 90 days-worth for only $30. Click on this link for details.

  • Jorge ochoa from Santa Ana ca.

    Posted on 7/3/2015 6:23:31 PM

    Would like to see video on wiring speakers to amp.

  • Chad from Illinois

    Posted on 7/13/2015 1:29:07 PM

    Do I splice the receivers harness in with the amplified speaker wires and vehicle harness?

  • Buck Pomerantz from Crutchfield

    Posted on 7/14/2015 12:16:38 PM

    Chad, Not quite. The speaker wires coming from the amplifier's outputs hook up to your vehicle's harness connected to the car speakers. The only connections used in the receiver harness are the power connections for the receiver and the remote turn-on lead for the amplifier.

  • paul from philadelphia

    Posted on 7/18/2015 6:57:21 PM

    Yeah but if you don't splice it with the wires from the receiver to then the fade wouldn't work or balance either on the receiver

  • Buck Pomerantz from Crutchfield

    Posted on 7/19/2015 12:00:07 PM

    Paul, The outputs of the receiver connect to the amplifier's inputs via RCA cables. The balance and fade controls on the receiver work just fine. This article merely spotlights one way of connecting the amp's outputs to speakers using a multi-conductor cable.

  • Galo Chaquinga from Ecuador

    Posted on 7/26/2015 8:31:42 PM

    Greeting I'm from Ecuador make a purchase in one harness OESWC- LAN amazon 29 H and desire to be able to help me a graphic indicating to serve some cables that have nothing printed thanks for your help

  • Buck Pomerantz from Crutchfield

    Posted on 7/27/2015 2:52:19 PM

    Galo, That steering wheel control harness will be specific to your vehicle and aftermarket receiver, and I don't have the technical knowledge on how to hook it up. Why don't you visit Axxess International, the makers of that harness, and see if you can get wiring diagrams and tech support from them.

  • adam from mesa

    Posted on 7/27/2015 3:15:55 PM

    I need the wiring diagram for my factory speaker wire colors for a 2012 chevy traverse ls model non bose

  • Buck Pomerantz from Crutchfield

    Posted on 7/27/2015 3:51:13 PM

    Adam, Sorry I don't have access to that information for that vehicle. Try contacting your local Chevy dealership, they may help.

  • Matt

    Posted on 8/1/2015 9:10:04 AM

    Hi, My rear speakers are currently a couple kickers that are connected to an amp. I had it all installed by car toys. Now I want to upgrade my two rear speakers to the infinity kappa 693.11i . To do that is it something as simple as just unplugging the wire from the old speakers and plugging them into the new ones? I would love to just do it myself and save all that money on install. Thanks for the help!

  • Buck Pomerantz from Crutchfield

    Posted on 8/2/2015 11:55:45 AM

    Matt, If I understand you correctly, and everything fits your vehicle, then yes you can replace older aftermarket speakers with new ones and use the older wiring. If you purchase your new speakers from Crutchfield, we'll include our vehicle-specific instructions free with the order, that illustrate in detail how to do the installation yourself. You can also purchase a MasterSheet separately for just $10.

  • Patrick from Mesa

    Posted on 8/18/2015 8:11:35 AM

    So if we do decide to run new speaker wire directly to the speakers, what do we do with the now unused wire that's connected to everything else? I'd imagine it wouldn't be easy to completely remove it.

  • Buck Pomerantz from Crutchfield

    Posted on 8/18/2015 11:30:05 AM

    Patrick, Normally you'd leave the factory wiring in place, making sure conductors cannot touch together or metal by covering the ends with electrical tape.

  • Thomas from Grand rapids MI

    Posted on 9/9/2015 5:25:31 AM

    So instead of re connecting the stock speaker wire harness to my new deck I splice them into the amp with the two RC cables from the amp to the deck? Or do u splice it like a 3 way?

  • Buck Pomerantz from Crutchfield

    Posted on 9/9/2015 2:20:13 PM

    Thomas, Let's see if I can explain the signal flow this article describes a little better. The preamp outputs of your receiver connect to the amplifier's inputs via RCA cables. Then, using a multi-core conductor, the outputs of the amp connect to the factory speaker wires accessible behind the receiver. The receiver's speaker outputs should remain unconnected to any wiring.

  • Matt from Waterloo

    Posted on 9/15/2015 11:25:13 PM

    I want to hook my back speakers up to my 900 watt Kenwood amp..but I don't want to blow my speakers...can you give me tips on what Ishould set the gain and volume on the amp to.

  • Buck Pomerantz from Crutchfield

    Posted on 9/16/2015 10:20:37 AM

    Matt, I think that most speakers would blow up if subjected to that much power no matter how the amp's gain was set. But not knowing exactly what amplifier or speakers you have make it impossible to give advice on how to wire them together.

  • Jacob Rogers from Nacogdoches

    Posted on 9/20/2015 12:34:37 PM

    What gauge speaker wire do I need for a pair of 12s that are 1400 rms each?

  • Buck Pomerantz from Crutchfield

    Posted on 9/20/2015 3:45:00 PM

    Jacob, Either 14-gauge or 12-gauge speaker wire will work well for your subs.

  • Keith from Puyallup

    Posted on 10/7/2015 3:01:24 PM

    So do I connect the 9wire cable from the amp to the head unit harness that came with the head unit, the aftermarket harness that is connected to the head unit harness, or to the car's original harness?

  • Buck Pomerantz from Crutchfield

    Posted on 10/8/2015 9:24:31 AM

    Keith, The 9-conductor cable used as in the article will have one end connecting to the amplifier's speaker output terminals and the remote turn-on terminal. The other end connects to the vehicle's harness, which connects to the speakers, and the turn-on lead in the receiver's harness.

  • Shawn

    Posted on 10/10/2015 12:20:12 PM

    if the amp I am running the speaker cable from is getting the radio signal VIA through line output of another amp [Daisy Chained] {because already have a mono and a 2 channel amp running to receiver} will wiring the cable from the amp into the receivers harness still work?

  • Buck Pomerantz from Crutchfield

    Posted on 10/12/2015 10:32:56 AM

    Shawn, Only one conductor of the 9-conducter cable goes to the receiver's harness - the 12-volt remote turn-on signal for the amp to turn on with the receiver. The other 8 connect to the vehicle-specific harness (usually free with the receiver) that goes to the vehicle's speakers. In this setup it doesn't matter where the amp gets its signal, direct from the receiver or daisy-chained from another amp.

  • Shawn

    Posted on 10/13/2015 9:42:58 PM

    Yea I think I got it now say forward is into receiver and back means out. I cut the speaker wire that run forward toward receiver then connect the speaker wire to the wires that are running back toward vehicle harness. is that bout right?

  • Buck Pomerantz from Crutchfield

    Posted on 10/14/2015 2:54:08 PM

    Shawn, Your usage of the words "forward' and "back" when describing signal flow is confusing, but I'll try and straighten things out. Eight of the wires coming from the receiver harness are the speaker outputs of the receiver and, using this wiring system, you no longer need them so they can be cut or taped so they won't make any contact with metal. Eight of the wires coming from the amplifier's speaker output terminals, via the 9-conductor cable, connect to the vehicle harness which connects to the vehicle's speakers.

  • shawn

    Posted on 10/15/2015 11:03:31 PM

    so you would cut right after the receiver harness which is after vehicle harness and connect the amp wire to the speaker wire heading away from receiver toward the cars receiver taping or capping the wires hanging out of the receiver that are no longer in use? wow, that is one giant run on sentence right there. Oh and the remote start wire goes to the receiver too? well I got to other amps with remote start so I guess it won't be to hard to figure out where they go.

  • Chad Brooks from Renton

    Posted on 10/21/2015 7:04:48 PM

    I think I'm starting to understand this. So right now I have one amp hooked up to my speakers/subs. I'm about to install a 4 channel amp for my speakers. I think I'll go ahead and get a 9 conductor cable , so I run that up behind my deck, clip the current speaker connections, and then attach the 8 speaker cables to the car side speaker wires and leave the speaker wires coming out of my deck alone right?

  • Buck Pomerantz from Crutchfield

    Posted on 10/22/2015 10:07:48 AM

    Chad, Sounds right to me.

  • Jody Treft from Liberty

    Posted on 10/24/2015 6:41:19 AM

    Disconnect the factory speaker wires from the head unit and connect factory speaker wires to amp speaker wires. The RCA output from the head unit to the amp inputs sound from the amp to the speakers? If I understand correctly, my amp is 75 watts x 4 @ 4 ohms I can do this? But if I wire it 160 watts x 2 @ 4 ohms I should run new speaker wires from the amp to the speakers?

  • Buck Pomerantz from Crutchfield

    Posted on 10/26/2015 11:12:04 AM

    Jody, We recommend for amplifiers with over 75 watts RMS of output per channel to go ahead and run new 14- or 16-gauge speaker wires directly from the amp to each speaker

  • Alex from Charleston

    Posted on 10/26/2015 4:30:07 PM

    If I connect an amplifier to my aftermarket door speakers, can I still use the speaker outputs from the back of the radio for more smaller speakers. Such as tweeters?

  • Buck Pomerantz from Crutchfield

    Posted on 10/27/2015 10:52:46 AM

    Alex, Yes you can.

  • Duncan

    Posted on 11/6/2015 2:13:01 PM

    So I have a 2011 F-150 with the Sony system w/o navigation. I bought a Pioneer AVH-X4700BS HU, Rockford 1683 door speakers, and a Rockford P3SD4-12 sub, all being powered by a Rockford Prime 600X5 amp. How will I connect the new door speakers to the new amp while bypassing the factory amp?

  • Alexander Hrabe from Crutchfield

    Posted on 11/9/2015 3:43:56 PM

    Duncan, you'll bypass the factory amp by using RCA outputs from your new head unit to the inputs on your new amp, then running new speaker wire to each speaker. If you'd like to use the factory speaker wire, you'll need to be able to make sense of factory color designations. We can help you with that. If you bought your gear from Crutchfield, you can call Tech Support for free help troubleshooting your system. If you purchased your equipment elsewhere, you can still get expert Crutchfield Tech Support - 90 days-worth for only $30. Check out our tech support page for details.

  • Montana Page from Grand blanc

    Posted on 11/11/2015 10:27:23 PM

    So do you run the speaker wire from the 4 new speakers, instead of the dash to the amp and then connect them to the harness then plug into radio? (including already plugging in the rca cables)

  • Buck Pomerantz from Crutchfield

    Posted on 11/12/2015 3:00:57 PM

    Montana, In the wiring system described in this article, no new wires are run to speakers. RCA cables carry the signal from the receiver to the amplifier. A 9-conductor cable carries four amplified channels from the amp's output to the vehicle's harness, which connects to the speakers via the factory wiring. Sorry if that's unclear. We're working to improve the illustration and messaging to make it all easier to understand.

  • Neal Green from Montgomery

    Posted on 11/16/2015 8:10:14 AM

    Buck, your patience is admiral. I found that drawing out each step you described makes better sense than trying to sort it out in your brain. Lot of redundant questions being asked.

  • Angel from Philadelphia

    Posted on 11/25/2015 10:27:20 PM

    Can this work with a 2 channel amp. 4 Door speakers and how?

  • Jeff from Altamonte Springs

    Posted on 11/26/2015 11:56:30 AM

    What would happen if I run this 9 wire loom from amp and splice into the posi tap connectors already connected to aftermarket radio/harness? Would this allow the radio to operate if the amp was not on or allow me to install toggle switch to turn off/on amp and listen thru aftermarket radio without amplification? I would think if I discarded to wires coming out of receiver and taped them off and instead wired this loom to the harness it would only work if amp is on. Will my thought of connection to existing harness wires affect something negatively?

  • Buck Pomerantz from Crutchfield

    Posted on 11/30/2015 1:12:47 PM

    Angel, Yes you can run four speakers with a 2-channel amplifier, but you'll lose the ability to "fade" your music from front to rear. You'd connect both left front and rear speakers to one amp channel and the right front and rear speakers to the other. The vehicle harness distributes the amplified signals to the four speakers.

  • Buck Pomerantz from Crutchfield

    Posted on 11/30/2015 1:38:43 PM

    Jeff, You should never connect the outputs of two amplifiers together - in your case a receiver's amplified output and an amplifier - one will burn out the other, or both. The wiring scheme described in this article is for a system where the power comes from the amp and the receiver's amplified outputs go unused. I suppose one could fashion a system that could switch between an amplifier's output and a receiver's powered output, but I see no benefits to such an arrangement.

  • Shawn

    Posted on 12/8/2015 2:32:07 AM

    My aftermarket amp runs 75x4 at 2ohms if I go the route of using the existing wiring will this work or should I run all new wiring

  • Shawn

    Posted on 12/8/2015 3:14:20 AM

    Sorry my speakers are 4ohms I would like to wire 2 speakers in Paralell to get a 2ohm impedence but needed to know if that is possible with using the stock speaker wiring

  • Buck Pomerantz from Crutchfield

    Posted on 12/9/2015 11:54:38 AM

    Shawn, It's unclear what you want to accomplish here. If you want to run two speakers off each of your amp's four channels, eight speakers total, then yes, you can do that using two 9-conductor cables connecting the amp to the vehicle harness. Just connect two speakers, left dash and door speakers, for example, to each amplifier output terminal. If you meant to bridge your 4-channel amp to 2-channel operation and run four speakers, two on each bridged channel, then it probably isn't possible. Most amplifiers are not stable driving a 2-ohm load when bridged. If your amp can, you can use this connection method but you'll lose the ability to "fade" your music from front to rear. You'd connect both left front and rear speakers to one bridged channel and the right front and rear speakers to the other. The vehicle harness will distribute the amplified signals to the four speakers.

  • Rick Stringfellow from Fairview hts

    Posted on 1/7/2016 5:04:22 PM

    I have two 18"Dvc2ohm SA subs and 2 amps 1 fosgate p10001bd an a JL Audio 10001v2

  • Buck Pomerantz from Crutchfield

    Posted on 1/8/2016 3:43:29 PM

    Rick, Not knowing the RMS power rating of the subs, I can't make a safe wiring recommendation.

  • Hysheem Perkinson from columbia

    Posted on 1/20/2016 6:07:57 AM

    im wanting to put 4 35 watt 5 inch speakers at 35 watts and 4 6.5 inch speakers 50 watts each how would i go about wiring these to an amplifier and can i use my stock wiring my front speakers are the 6.5 and my rear are the 5 inch the rest will sit in a custom made center console and is it best to use a 2 channel or 4 channle amplifier

  • Buck Pomerantz from Crutchfield

    Posted on 1/21/2016 10:38:13 AM

    Hysheem, You can certainly connect an amplifier's outputs to your front and rear speakers via a 9-conductor cable to the factory wiring behind the receiver. You'll have to run new speaker wires for your custom center console speakers, though. It's best, for control and level balancing, to have each speaker powered by a single amplifier channel. For the 8 speakers you describe, that means two 4-channel amps.

  • jordan from montgomery

    Posted on 1/31/2016 1:22:17 PM

    Here is my scenario: 2014 LTZ Tahoe, Bose speakers, using bose amp. Rockford 12's on 1500.1 amp in back. I am about to replace the door speakers and amplify them. Here is how I am going to do this, correct me if wrong, (FYI I am mounting 4-channel amp beside the mono-amp in the back) I will run 2-sets of RCA's from the head unit back to the 4-channel. Hook the power/ground into the distribution black in the back for power. Connect the remote wire to the remote wire ran to my existing amp back there already. THEN, run all 8 speaker wires (spliced from the harness up front, to the back of the truck into the correct speaker inputs on the 4-channel amp. I came to 8 speaker wires total , by this logic: front DOOR speakers - 4 speaker wire FRONT +/- AND +/- rear DOOR speakers - 4 speaker wires REAR +/- AND +/- Let me know if this will work, thanks

  • Buck Pomerantz from Crutchfield

    Posted on 2/1/2016 1:47:54 PM

    Jordan, Hopefully you meant to say you'll run the speaker wires from the harness to the amplifier's speaker outputs, not inputs - but it sounds like you're on the right track.

  • Haylee from Fortuna

    Posted on 2/10/2016 9:06:57 PM

    Im trying to hook up my pioneer AVIC X850BT to my already stock bose supreme stereo in my 2003 350z i get the pioneer to turn on but nothing but a buzzing noise out of my speakers how do i fix this?

  • Buck Pomerantz from Crutchfield

    Posted on 2/12/2016 10:26:23 AM

    Haylee, If you had purchased your gear from Crutchfield, you would have been advised about the special harness you need to hook up your new receiver to your car's factory amplifier. And, you could call Tech Support for free help troubleshooting your system. Their toll-free number would be on your invoice. If you purchased your equipment elsewhere, you can still get expert Crutchfield Tech Support - 90 days-worth for only $30. Click on this link for details.

  • Wayne Roper from London

    Posted on 2/13/2016 5:39:25 PM

    I understand the concept of using your 9 wire loom to splice into the main receiver harness, but what if, like me, you intend to run all new 12 gauge wiring to each speaker from a 4 channel amp? This option will obviously render the stock wiring redundant. So what happens to this? Is it simply disconnected from each speaker and taped up, in case of refitment of stock equipment later on, thus leaving it intact on the receivers harness. Or are the speaker wires cut at the harness to isolate them from the receivers signal? The way I understand it is, the RCA's will carry the signals down to the amp, and then the amp will send these signals to the speakers. Therefore the wiring at stock can be left alone and out of the way. Am I right?? Thanks.....

  • Buck Pomerantz from Crutchfield

    Posted on 2/14/2016 11:34:49 AM

    Wayne, When replacing speakers and wiring, after disconnecting the factory wiring from the speaker, you can leave it installed as it was. Make sure and secure, with nonconducting tape or tie-off, any wiring connector from making contact with metal, which could cause interference or damage the receiver.

  • Glen from Hopatcong

    Posted on 2/20/2016 5:39:56 PM

    my car came with a factory amp that i would like to replace, (I will also be replacing the head unit) the good thing is that all the wires from the head unit to the amp, and then from the amp out to the speakers are all located in one spot under the back seat (where the amp is mounted). My question is, can I use the factory wiring to get the speaker signal from a new head unit to the new amp,or do I have to run new RCA cables. It seems using the wires that are already there would save me a lot of labor

  • Buck Pomerantz from Crutchfield

    Posted on 2/22/2016 10:07:18 AM

    Glen, Not knowing what vehicle you have makes it pretty hard to answer any questions about its wiring. If you're going to replace the factory amp with an aftermarket amp, then you can probably use the factory speaker wires connected to your new amp's outputs. I would imagine that you'll probably have to replace whatever signal wiring the vehicle uses with new RCA cables between the new receiver and amp.

  • Justin Smith from jacksonville

    Posted on 4/12/2016 10:30:24 PM

    My rcvr only has 2 channel pre-amp outputs. I want to use one for a sub, leaving me with one set for either the front or rear deck. Both are 6x9s. Both have same power output. Which speakers would you recommend I amplify, the front or rear?

  • Buck Pomerantz from Crutchfield

    Posted on 4/13/2016 9:21:59 AM

    Justin, I recommend amping the front speakers, and drive the rear speakers off the receiver's speaker outputs, using them for "rear-fill" giving your big front stage stereo image some depth.

  • Chris

    Posted on 4/16/2016 2:13:04 PM

    I'm connecting a fosgate r500x-1d amp(500watts rms - 300x1@4ohms/500x1@2ohms) to 2 12" kicker compR rated 500 watts rms at either 2/4 ohms. Should I run them in parallel or series or can I just run the wiring from the subs directly to the amp?

  • Buck Pomerantz from Crutchfield

    Posted on 4/19/2016 1:35:47 PM

    Chris, Those subwoofers are DVC 2-ohm subs that each uses a switch instead of a jumper wires to change impedance between 1 ohm and 4 ohms. I recommend setting yours to the 4-ohm setting and wiring your subs to that amp like this. In this setup, the two subs are wired together in parallel, and you would achieve the same results if you wired both subs to the amp separately.

  • James from MN from Hastings mn

    Posted on 4/28/2016 10:46:18 PM

    Your article was very clear and I appreciate your help. I do have a specific question as it relates to my car audio. Currently I am using a LOC for my amp to power a sub in back and I have retained the factory head unit. If I were to want to power the 6x9s in back and the 4x6s in front, how would I go about wiring a separate 4 channel amp. Thanks

  • Buck Pomerantz from Crutchfield

    Posted on 4/29/2016 2:06:57 PM

    James, Now that you're familiar with what an LOC is and what it can do, perhaps you're ready to step up to a multi-channel version, like AudioControl's LC6i. It takes the signal from your factory radio's front and rear speaker wiring and creates adjustable preamp-level outputs for your full-range speaker amplifiers and your subwoofer amp.

  • Jose from Palmdale

    Posted on 5/5/2016 2:56:08 AM

    hello, I already have an amplifier with 2 subwoofers, how am i going to power another amp to be used for my speakers? Thanks in advance for the answer

  • Jeremy Kellison from Ocala

    Posted on 5/5/2016 6:55:41 PM

    So I am installing 4 new speakers to a 4 channel amp to my factory radio. I'm adding a 4 channel line out convertor to accept the rcas. I would then just wire the line out convertor into my wiring harness thats there and just run the rca cables into that and then wire in my speaker wire into the harness to my amp? I have an amp already for my subs just adding a new amp for my speakers

  • Buck Pomerantz from Crutchfield

    Posted on 5/6/2016 1:35:34 PM

    Jose, When running multiple amplifiers, you should use a distribution block to safely distribute power to all the amps in your system. Just make sure the primary power cable, from the battery to the block, is large enough to accommodate the total power draw of all the amplifiers.

  • pete from buddlake n,j

    Posted on 5/24/2016 3:35:50 PM

    hey how are you today,i recently bought speakers for you guys,,they are Kicker 40CS674 6-3/4" 2-way car speakers,,they are working great,but i have one question i have read this little article on your site,,,,The Rockford Fosgate System adds a 300W amplifier and an 8" subwoofer in an sealed enclosure, located in the trunk. The subwoofer is a dual-voice coil design. The amplifier powers the front speakers and the subwoofer. The receiver powers the rear speakers only. as you can see,the info is for a nissan sentra 2006,,now my question is,,how or can i get power from the amp to the rear speakers,,,,i had skpoken to Garrett when i bought my speakers,,,,

  • Juan from Minneapolis

    Posted on 5/25/2016 12:44:53 AM

    How about if I wanna have component speakers of the front and coaxial on the back? And also using a 75W RMS per channel is that going to be too much for 18 or 20 AWG factory wires?

  • Buck Pomerantz from Crutchfield

    Posted on 5/25/2016 9:07:49 AM

    Pete, The Rockford Fosgate system in your Sentra has an amplifier that drives the front speakers and subwoofer. There are no provisions for connecting more speakers to it. If you want more power for your rear speakers, add a 2-channel amplifier to your system.

  • Buck Pomerantz from Crutchfield

    Posted on 5/25/2016 10:59:11 AM

    Juan, You run speaker wiring to components the same way as coaxial speakers except the factory wiring at the speaker end goes to the crossover input, and then new wire needs to be run to each tweeter and midrange speaker. Using factory speaker wiring for a 75-watt amp should be okay. It's when you have more power than that - 85 or 100 watts say - is when you'd benefit with thicker wire.

  • James from St Petersburg

    Posted on 6/3/2016 11:16:11 AM

    Hi Buck, Let me explain my application and if you could, tell me if how I would be using this is correct in my set up if you could. My equipment is being installed in a 2012 Nissan Frontier is as follows: JBL MS-8, a JL Audio Xd700/5, a Kenwood DDX6702s receiver, Hertz HSK 165.5 6 1/2 components for for front doors and dash, Hertz ECX 130.5 5 1/4 2 way speakers for the rear doors, and a JL Audio 10w3v3-2 for sub. I run a rca cable via the Kenwood pre amp output (just a left and right front channel because the MS-8 only requires a two channel input) to the MS-8 input. I will then run RCAs from the MS-8 outputs to the XD7005 inputs. From there, I wire the XD700/5 speaker outputs to the EFX 9- conductor cable (the front speakers will be wired to the component crossover from the XD700/5 front left/right speaker outputs and then the crossovers left/right woofer/tweeter output to the appropriate front left/right speaker wires in the EFX 9-conductor. Subwoofer will be wired directly from XD700/5), I then run the EFX 9-Conductor cable to the rear of the Kenwood receiver and wire it directly to the wiring harness speaker wire outputs which is then plugged into the factory wire harness that the speakers will be connected to from the factory locations. Also, how is the EFX cable color coded and is it to each specific vehicle? Is this how I would correctly utilize the EFX 9-conductor wire and eliminate the need for separate speaker runs? Thanks in advance for your reply!

  • Francisco Pando from Great Bend

    Posted on 6/28/2016 6:43:38 PM

    I want to hook up a sound processor to my head unit and then run that to an amp. This way all four door speakers are taken care of. At some point in the future I ant to ad a sub in the trunk. My question is how many channels would I need on the processor as well as the amp?

  • Buck Pomerantz from Crutchfield

    Posted on 6/29/2016 10:46:56 AM

    James, Sorry I haven't responded sooner, but it sounds like you already understand this wiring technique.

  • Buck Pomerantz from Crutchfield

    Posted on 6/29/2016 11:17:33 AM

    Francisco, The number of channels needed for a digital sound processor depends on how many speakers you want to run and how many output channels your receiver or factory amplifier has. For instance, if you have four speakers (front left, front right, rear left, rear right) you'd need a 4-channel processor. But if you want to add a sub later, you'd want to get a 6-channel processor. The processor will create the subwoofer channel outputs from the other inputs. You can use a 4-channel amplifier to run your four door speakers, and add a mono amp for a sub later on. Or you could buy a 5-channel amp and leave the sub channel unconnected until you get a subwoofer.

  • Rob from York

    Posted on 7/29/2016 9:40:41 AM

    I will be using a factory head deck and a compact 4 channel amp to add power to after market speakers... I haven't ordered the amp yet but I know my factory head deck doesn't have rca's... I get the hook up you are describing... How would what I am looking to do be spliced in? Thanks!

  • Buck Pomerantz from Crutchfield

    Posted on 7/29/2016 1:04:26 PM

    Rob, Your question brings up a great point: I should show how to hook up an amp in a factory system with no RCA outputs, like yours. Step one: get an amplifier with speaker-level inputs. Referring to the photo in this article, instead of the RCAs pictured at the upper right, you'd use the speaker wires coming out of the radio harness (that we snipped off for the illustration). Using another of those 9-conductor cables, you'd connect from the radio harness to the amp's speaker-level inputs.

  • Graham from Woodstock

    Posted on 8/27/2016 2:56:01 PM

    Hi, I recently put a new stereo head into my 1996 Hona Civic Cx, soldering the head unit wires into the original system wires and leaving it at that. after that I put in two new kickers in the front two doors and two new kickers in the rear two outlets. all soldered into the original wires. the speakers sound great but when i max out the volume the sound sometimes cracks and even when maxed it isnt as loud and doesnt sound as great as i want it to. I would like to fix this by adding an amp but im not sure how to wire it in. as the article states id like to be able to just wire it to the head unit... but would that actually do anything for me? I just want to make my speakers get to full potential without doing a butt ton of re wiring and would love to be able to use the original factory wires plus a little more. this whole situation confuses me and ive tried to do as much research as possible but im still not sure exactly how to fix my problem. sorry if this is poorly worded or stated in an awkward way, i can re-word it if need be. thank you, graham also i am thinking about adding a sub in the near future, and would like to be able to add that if needed. but again, thats not exactly the issue at hand.

  • Buck Pomerantz from Crutchfield

    Posted on 8/29/2016 10:04:52 AM

    Graham, I'm sorry this article isn't clearer about how to wire an amp into a car system. You connect the aftermarket receiver's RCA outputs to the amplifier's inputs via RCA cables. Then you connect the amp's outputs to the speaker wires of the vehicle harness via a 9-conductor speaker cable. Maybe looking at the photo and its captions will help you visualize how this saves running speaker wire throughout the car to each speaker.

  • Viv

    Posted on 8/29/2016 6:12:00 PM

    Hi, Excellent article firstly! I have a query however. I have installed a 140rms x 4 amplifier (nominal power) to my new front door speaker DLS components which can take 140rms nominally as well. However they don't sound any much louder than when my stock was amplified before the bass starts to sound muddy and distorted. And the stock speakers were rated at 35w RMS! I've matted the doors, checked the polarity and those are fine. However the speaker wires are connected via the stock location at the receiver end as explained in this article. Can this really be the cause of the new speaker components sounding muddy before its rated power (140w RMS each) ? It sounds like 40w RMS power to me. The speaker wires from the amp and RCA cables from the Headunit are all run together next to each other as well. Not sure if that'll pose an issue!? Thanks

  • Buck Pomerantz from Crutchfield

    Posted on 8/30/2016 12:45:46 PM

    Viv, Factory speakers often have low impedance and high sensitivity and play louder than aftermarket speakers. A speaker's power rating has no bearing on how loud it will play - that depends on how much power the amp sends it and how sensitive the speaker is to that power. I can't tell why yours sound muddy, but I doubt it has anything to do with the wiring. Trying to push 140 watts through factory wiring may result in some power loss but shouldn't introduce distortion. And running the RCAs and speaker wires together should be okay - it's the power wiring that can induce noise that should be kept separate from the signal wires.

  • Jay from Indy

    Posted on 9/2/2016 9:15:19 AM

    Nice write-up. I am wondering if it is possible to leave four orig speakers (1-4)connected directly from the head unit AND ALSO add a 4 channel amp to feed four additional speakers (5-8). The amp and speakers 5-8 would function with the key on-vehicle running, while the orig speakers 1-4 would serve as the quieter camping speakers when parked with less power drain on my aux battery. Would this be feasible?

  • Buck Pomerantz from Crutchfield

    Posted on 9/3/2016 10:22:11 AM

    Jay, I say go for it, I can't think of a reason it wouldn't work.

  • Colton Hillman from Linden

    Posted on 9/13/2016 7:49:33 AM

    I have a big Kenwood amp in my 84 f150 powering my subs. I got told if i wanted to amp the factory speaker doors, do NOT plug it into my high powered amp, but get a smaller amp just for the door speakers. how would i go about wiring in another amp if my RCA cable are running to the big amp? Do i just run RCA cables from the output on the big to the input of the small?

  • Buck Pomerantz from Crutchfield

    Posted on 9/13/2016 10:38:37 AM

    Colton, If your subwoofer amplifier has preamp-level RCA outputs, you can use them to provide input for a second amp.

  • Logan leatherwood from Boaz

    Posted on 9/27/2016 4:36:37 PM

    Ok so I'm trying to connect my iPad to my car speakers and sub. I have an amp and I I have the isimple universal car kit , metro 70 1721, and wiring. Is that all I need? I don't have a head unit.

  • Buck Pomerantz from Crutchfield

    Posted on 9/28/2016 1:19:36 PM

    Logan, I'm not familiar with that iSimple kit, but if it makes your iPad's audio output available for an aftermarket amplifier, that's good. Assuming you have signal wiring, from the iSimple kit to your amp's inputs, and power wiring for the amp, this is a good opportunity to use 9-conductor speaker cable from the amp's outputs to the Metra harness. How're you fixed for connectors and installation tools?

  • Corey in Texas from Denison

    Posted on 10/18/2016 1:41:38 AM

    i have 2 12" kicker comp S bridged on channel 3 and 4 on my SslDG41600, 1600w 4ch amp.I have 2 kicker 6.5" 4ohm 2ways. I dont want to tear out my Santa Fe's Infinity 6.5 as they work fine on the stock head and im still paying on the car. so i bought 2 boxes for the 6.5s. can i hook them up separately on channels 1 and 2? Or do i run them in parallel to channel 1?

  • Buck Pomerantz from Crutchfield

    Posted on 10/18/2016 3:07:18 PM

    Corey, You can definitely hook up each of those speakers to a separate channel of that amp, that'll be the preferable way. Be sure to secure the speaker boxes to your vehicle. You don't want them flying around dangerously in the event of an sudden stop or accident.

  • Joshua from New Orleans

    Posted on 10/18/2016 8:55:04 PM

    Buck, thanks for the article. Much appreciated. It helped me hook up my system. One question about this method though. What would need to be done if you have a navigation receiver that only sends out Nav audio and Bluetooth phone audio over the pair of front speaker wires of the receiver? If these wires are cut/taped, this would result in no nav/bluetooth phone audio. I know of a few Pioneer units where this is the case. Would it be possible to connect the front speaker wires of the receiver to the front speaker wires coming from the amp with the amplified sound and front wires of the aftermarket harness? Or would this damage the receiver or speakers? Thanks in advance.

  • Buck Pomerantz from Crutchfield

    Posted on 10/19/2016 3:59:37 PM

    Joshua, When you splice amp connections into the receiver's RCA outputs and speaker wiring, like this article describes, whatever the receiver tries to send out to the front speakers will pass through the amp and on to the speakers - you shouldn't lose your Nav directions or phone audio. Now in some systems with factory receivers and amplifiers this won't work because either the receiver shuts down because it doesn't see a speaker load on its output, or the Nav and Bluetooth audio originate in the car's computer system and never travel through the receiver's output wiring. And under no circumstances should you connect the output of a receiver to the output of an amplifier - that will damage something.

  • Keith Parker from Bastrop La. 71220

    Posted on 10/27/2016 11:35:42 PM

    I bought a pioneer stereo from you through my Mothers name Melba Parker. I bought it after problems I had Because it only had 2 channel for speaker and two RCA jacks for a sub.I had to unhook it from a 4 channel Crunch amp. and I can"t get all channels to work now after hooking it back up. My question is what should I do to make sure all of my channels are working or might have a bad connection somewhere or bad wires. I tried to check my speaker outputs with a test light but could"nt figure out if they have power to them. Thanks for your advice!

  • Buck Pomerantz from Crutchfield

    Posted on 10/28/2016 10:40:28 AM

    Keith, One of the perks of buying gear from Crutchfield is that you get free Tech Support. Their toll-free number is on your invoice. Call them for free help troubleshooting your system. Click on this link for more details.

  • Jason from Atlanta

    Posted on 11/11/2016 4:27:10 AM

    I'm my truck I have 2 tweeters and four 6.5 coaxial speakers in the doors. Can I wire the four 6.5 speakers to a 4 channel amp and the 2 tweeters to the head unit? I have JVC 212bt head unit.

  • Buck Pomerantz from Crutchfield

    Posted on 11/11/2016 10:27:59 AM

    Jason, I don't see why not. If you use the method described here, using the factory wiring for the four main speakers, you could take the left and right front speaker wires from the radio harness and splice on new speaker wires for your new tweeters.

  • David from Muskegon

    Posted on 11/24/2016 10:45:25 PM

    I have a Memphis(mono block) amp 16-ST500D which can be made 2ohms min and I have two boxes with a 12" JL Audio in each. Could you show me a diagram to properly wire them for one box installation and also for two box installation. Thx

  • Buck Pomerantz from Crutchfield

    Posted on 11/28/2016 11:56:37 AM

    David, Not knowing exactly what subwoofers you have make it impossible to give advice on how to wire them together. JL Audio makes 2-ohm and 4-ohm loaded sub enclosures. If you want a question answered about your system, you must identify your equipment by model number as well as brand name

  • Dahita from Reston, VA

    Posted on 12/18/2016 7:30:53 PM

    Hello, Thank you very much for your article. I am struggling to get the factory amp working with the PAC RPK5 GM4101 and a Pioneer 4200; the sound comes out of all speakers but it sounds like it's not amplified (sound distorts at mid level). Yet the blue/white cable is plugged correctly, so I'm assuming the amp is on. The one thing I'm puzzled about is that there are 2 RCA cables labeled "Aux In" coming out of the main harness (big black plug); I connected them to the Aux input of my stereo but it makes no sense as it is already connected for Aux In with a Jack that works fine. Could these RCA be the ones you mention to connect to the stereo's speaker wires? like front or rear RCA from the stereo? Would this make my sound amplified again?

  • Buck Pomerantz from Crutchfield

    Posted on 12/19/2016 11:34:14 AM

    Dahita, A list of what may be wrong is long, starting with the fact that two inputs shouldn't get connected together (if that's what you have). If you bought any of your gear from Crutchfield, you could call Tech Support for free help troubleshooting your system. Their toll-free number would be on your invoice. If you purchased your equipment elsewhere, you can still get expert Crutchfield Tech Support - 90 days-worth for only $30. Click on this link for details.

  • Dahita from Reston, VA

    Posted on 12/19/2016 9:00:38 PM

    Thank you very much for your answer

  • Rogelio Montalvo from Harker Heights

    Posted on 1/24/2017 6:36:55 PM

    I chose to use the 9 wire connector but my front speakers are not working. My 9 wire connector is running from the amp directly to the vehicle harness. Do I need to do something different since I connected a pair of Kicker 40CSS694 6X9 component speaker system? All speakers are using the factory wiring connection at each door for all of my speakers. The rear speakers are working to include my subwoofer. I am at a lost..........

  • Buck Pomerantz from Crutchfield

    Posted on 1/27/2017 10:46:11 AM

    Rogelio, If you bought your gear from Crutchfield, you could call Tech Support for free help troubleshooting your system. Their toll-free number is on your invoice. If you purchased your equipment elsewhere, you can still get expert Crutchfield Tech Support - 90 days-worth for only $30. Click on this link for details.

  • Nunzio

    Posted on 2/13/2017 8:43:14 AM

    Hi, Can this be done to a 2016 Chevrolet Silverado Double Cab without Bose system; With 8" LCD Radio, by adding a Amp and using the existing speaker harness running to all four doors ?

  • Buck Pomerantz from Crutchfield

    Posted on 2/14/2017 10:13:20 AM

    Nunzio, This method of connection can be done in almost any system without a factory amplifier.

  • Calvin

    Posted on 2/23/2017 8:02:33 AM

    What is the correct speaker wiring pattern of wiring two amps that are strapped together?

  • Buck Pomerantz from Crutchfield

    Posted on 2/24/2017 9:28:23 AM

    Calvin, Amplifiers that can be strapped together in order to double the available power use proprietary connections that are different from the way most amps are wired. Each amp manufacturer does it differently - some use interconnecting cables, some use switches. The only way you can tell if your amps can be strapped together and how to wire them is by referring to their instruction manual.

  • Troy

    Posted on 3/8/2017 12:13:58 PM

    The article recommends running separate speaker wire from the amp to the speakers if exceeding 75watts RMS. I understand the hook up procedure for this. My question is...when you connect your speakers directly to your amp instead of splicing through the wiring harness, can you LEAVE the harness connections alone or do you have to physically cut the speaker wires? I'm going to be installing a new radio soon and speakers. I will connect all through the harness. When I add an amp, I want to wire the speakers from the amp. So just wondering if I can leave the harness speaker connections alone if I do that. This way I can go back to stock components if I ever want to. Thanks. Hope this all makes sense.

  • Buck Pomerantz from Crutchfield

    Posted on 3/9/2017 10:06:08 AM

    Troy, You can leave the harness alone, for just the reasons you mention. You will disconnect the factory speaker wires at the speakers, whether unplugging them or by cutting the wires. Just be sure to tape off any exposed conductors so they can't short by touching anything metal.

Ask an expert advisor

No pressure, no commission — just lots of good advice from our highly trained staff.

Find what fits your vehicle

Can't find your exact vehicle?