Connecting your speakers to an amp

Tip: You can use your vehicle's factory wiring


Buck Pomerantz

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.

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Sending a signal from a receiver to an amplifier's input via RCA-type cables or the speaker-level outputs is straight forward and simple enough, but getting the amplified signal back to the speakers—well that's another matter. The speakers are usually in four different corners of your vehicle, and running separate new speaker wires to each 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 the amp to your speakers is to run the speaker wires to the harness that’s behind your receiver, where all your car’s speaker connections are accessible in one place.

Getting signal to the speakers

Normally, the speakers connect to the receiver through the receiver wiring harness behind the dash. You cut each speaker wire from the receiver's harness and reconnect it to a speaker wire coming from the amplifier. Then, the signal can flow from the amp to the speakers by way of the vehicle's original factory wiring. 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 them all at the same time.

StreetWires iCS920C multi-conductor cable

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

Some products to help you do it

Crutchfield offers a 12-foot and a 20-foot 9-conductor cable that helps simplify running 8 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 for sending the amp's output signal to the factory speaker wires.

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 over 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.

  • 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.

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