Amplifier wiring diagram

A typical 2-amp setup


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Amplifier Wiring Diagram

This simplified diagram shows how a full-blown car audio system upgrade gets wired in a car. The system includes a 4-channel amp for the front and rear pairs of full-range speakers and a mono amp for a subwoofer. Capacitors aren't usually necessary in a car stereo installation but we included one here to show how it would get wired into a system.

  • John

    Posted on 4/28/2015 8:10:38 PM

    If I had two amps running their own power lines straight from the battery, how would I wire the capacitor?

  • Buck Pomerantz from Crutchfield

    Posted on 4/29/2015 10:25:54 AM

    John, If your audio system is drawing so much power from your vehicle's electrical system that you need a capacitor, it should be connected to your subwoofer amplifier's positive power lead and ground. The diagram gives a generalized picture of how it connects. You'll need to refer to your capacitor's installation instructions for more details.

  • Jose Gomez from Queens , New York

    Posted on 5/3/2015 10:18:09 PM

    hi there, my questions is: I have 2 new Kicker - CS694 6" x 9" Coaxial Speakers with Polypropylene Cones, Handles up to 450W peak power (150W RMS) and Subwoofer 450W Pioneer 10", I want to hook up those together, but I need amplifier: How much power? and 3 or 4 channels?, help me please......this is for my work truck. thanks

  • Buck Pomerantz from Crutchfield

    Posted on 5/4/2015 12:38:11 PM

    Jose, You will need 3 amplifier channels to run this system, two for the front speakers and one for the sub. One of the neatest ways to get the amount of channels and power you'll need is to get a 5-channel amplifier, like the Kenwood Excelon X700-5, and bridge the front and rear channels to send 100 watts RMS to each of the full-range speakers, and run the subwoofer with up to 500 watts RMS from the subwoofer channel.

  • Elliott G Lemire from Canada

    Posted on 5/5/2015 1:32:02 AM

    So what if my Deck didn't have a 'Sub out'? I plan on using the Stock Deck, (it's all integrated with steering wheel, BT etc...) I've heard of a 'Hi / Low' Filter???

  • Buck Pomerantz from Crutchfield

    Posted on 5/5/2015 12:38:20 PM

    Elliott, You can add a subwoofer to a factory system by using a line output converter (LOC) or a subwoofer amplifier that has speaker-level inputs to get signal from the factory speaker wiring. Usually you splice into four wires - left positive and negative, and right positive and negative. The left and right signals get mixed together inside the amplifier to produce the single subwoofer signal. Your sub amp or powered subwoofer will have a low-pass filter that you must set to remove all high-frequency content and clean up the bass sound. Most people access the wiring at the vehicle's rear speakers, because it's easier to get at them there, but behind the receiver at its wiring harness is okay as well.

  • John from Nevada

    Posted on 5/12/2015 3:17:33 PM

    Buck, I have this similiar setup. In this diagram how would I connect an epicenter?

  • Buck Pomerantz from Crutchfield

    Posted on 5/12/2015 3:44:02 PM

    John, Processors like this get connected between a receiver and amplifier. In this case, the patch cables that come from the receiver's subwoofer output would plug into the Epicenter's inputs. The Epicenter's outputs would then go to the subwoofer amplifier's inputs. The Epicenter's power, ground, and remote turn-on lead will have to be connected in the same manner as your amplifiers. One thing to note, however, is that an Epicenter likes a full-range signal for its input - so if you use the receiver's subwoofer output, set it to full-range or set its low-pass filter to the highest frequency.

  • Nate from spring ntx

    Posted on 5/23/2015 8:08:55 AM

    what would give best performan if i have 2 500 watt 12s svc on a 1500 watt single fuse planet audio monoblock and a 3 way crossover as well as 2 2000 watt 15 dvc qpower on a 4000 watt mono block with 3000 compasitor

  • Derek from Texas

    Posted on 6/1/2015 1:14:26 PM

    I have a 2005 Mercury montego with 6 speakers. The rear deck has 2 kicker 6x9 css69. I have a Powerbass RTA-112 Single 12" powered sub. I want to replace the other 4 speakers with pioneer ts-a6885r. Will the Powerbass sub amp interfere with getting an amp for the 6 speaker?

  • Buck Pomerantz from Crutchfield

    Posted on 6/1/2015 1:53:53 PM

    Derek, The rear deck speakers in your '05 Montego with the 6-speaker system are actually subwoofers - the factory amplifier has a built-in crossover, so any replacement speaker you put in back there will only play bass. You can certainly add a powered sub to the system to improve the bass if the factory subwoofer amp isn't powerful enough for you. When it's time to upgrade the power for your full-range speakers, you'll only need to add a 4-channel amplifier to the system.

  • Abdel

    Posted on 7/9/2015 2:11:12 AM

    I plan on running this diagram with adequate measurements taking accounted for based off of all the other DIY tutorials and explanations provided by cruthcfield which I sincerely thank all of you for. However I have a side question about the 4 channel amp and speakers i plan on purchasing. If the 4 channel amp is rated at 1600 watts but 180 watts RMS at 2 ohms by 4, and the speakers i am getting are rated at 180 watts and 60 watts RMS (JBL GTO638 )... is it 60 watt RMS per speaker (meaning that the amp is adequate or is it 60 watt rms per speaker meaning that the amp could provide the 150% max power threshold? If there is an amp that you would recommend for these speakers please include it in the response. Thank you.

  • Buck Pomerantz from Crutchfield

    Posted on 7/9/2015 11:57:37 AM

    Jeremy, If you bought your amplifier at 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.

  • Buck Pomerantz from Crutchfield

    Posted on 7/9/2015 12:26:38 PM

    Abdel, Almost any 4-channel amplifier with between 45 and 90 watts output per channel will work with those speakers. I'm not sure your location, so I don't know what's available to you. You can contact a Crutchfield Sales Advisor for recommendations via phone or chat. The toll-free number and contact information are at the top of this page.

  • Casey from United States

    Posted on 7/13/2015 5:30:42 PM

    What if you are not able to connect 3 sets of RCA cables to your receiver? Is it safe to splice one pair of the RCA cables running to the 4 channel amp and run to sub amp? OR If the sub amp takes high level input, could you splice the speaker wire coming from the 4 channel amp and run to sub amp?

  • Buck Pomerantz from Crutchfield

    Posted on 7/14/2015 12:54:12 PM

    Casey, It is never a good idea to try and splice into an RCA cable, that may introduce noise and interference. In order to feed multiple amplifiers from a limited number of channels you can use Y-cords - adapter cables with a single connection on one end and two on the other.

  • CHRIS PAUL from Melbourne

    Posted on 7/21/2015 2:31:26 PM

    Hello I am having problems making my setup sound cleaner/ which boxes to use/ which amp to pair with subs/ wiring issues??? first i will list my setup as accurately as possible for you. head unit: basic pioneer no bluetooth. 2 pre amp outputs front aux and usb cost about $80kicker rcas from best buyoff brand rcasamps: kenwood 5 channel 1200 watt max, got from best buy for 250 normal price is 350power acoustic 2000 watt mono block, got from a friend for cheap :)subwoofers: 2 kicker compVR DVC 12 inch subwoofers2 power acoustics that i got with the 2000 watt amp. im assuming these speakers have somewhere around 600-800 rms EACHthe 2 front door speakers and tweeters in the camry are stock, i obviously want to change that eventually. the rear deck speakers dont work because i bypassed the stock jbl amplifier that comes with the car. so i bought a pair of polk audio 6x9s from best buy they were 149.99 for the pair. i think this model got discontinued but i like them they scream pretty loud. i have the polk audios hooked up to the kenwood 5 channel amplifier. i havent taken the time to switch the 6x9 polk audios with the rear decks that arent working. so the 6x9s are sitting on top of the rear deck sliding around LOL.on to the subwoofer setup. i have the 2 kickers compVR 12 inch hooked up to the kenwood 5 channel. i have them bridged .then i have the 2 12 inch power acoustics hooked up to the 2000 watt amp. i also have a scosche capacitor hooked up in the backi am running 4 gau

  • Buck Pomerantz from Crutchfield

    Posted on 7/21/2015 2:56:56 PM

    Chris, If you had bought your gear at Crutchfield, you could call Tech Support for free help troubleshooting your system. You can still get expert Crutchfield Tech Support - 90 days-worth for only $30. Click on this link for details. If you do, be prepared to identify your equipment by make and model number, not by what price you got it for.

  • Felix Harvey from Dyer

    Posted on 8/1/2015 1:35:17 PM

    I have a five channel amplifier that is powering four speakers and a sub. It has three 30 amp fuses on it so I am using a 100 amp fuse close to the battery. I want to add a mono amp just to power my sub that has two 30 amp fuses in it. Having two amps I know I will be adding a power and ground blocks and run 4 gauge wire from the battery. my actual question is what size fuse am I now going to need at the battery, or will it remain a 1oo amp fuse.

  • Clifton Bond from United States

    Posted on 8/1/2015 7:36:39 PM

    Thank you.

  • Keith from Winder

    Posted on 8/2/2015 12:56:21 PM

    I have a van I'm putting a 15" sub with a 1200 watt rockford fosgate prime with 4 RF 6 1/2" with a 600 watt prime and 4 RF tweets on a 300 watt prime the head unit has 3 sets of outputs. Is this the best way to hook it all up?

  • Buck Pomerantz from Crutchfield

    Posted on 8/2/2015 4:11:59 PM

    Felix, The in-line fuse on the power wire by the battery protects the wire and your car from fire in the event of a short circuit. If you're using a 4-gauge wire from the battery to a distribution block, then a 100-amp fuse should be okay. If you find that your amps are struggling to make power, you may want to consider upgrading to a 2-gauge wire and 150-amp fuse.

  • Buck Pomerantz from Crutchfield

    Posted on 8/2/2015 4:42:50 PM

    Keith, Are you planning on installing four full-range speakers and then adding more tweeters? Or are these Rockford Fosgate components that come in a set and have their own crossovers? If that's the case, then you won't need that third amplifier. This wiring diagram shows a typical setup for running four full-range speakers and a subwoofer. If you want to add two tweeters to this kind of system, you'll have to get signal for them using Y-cords on the front full-range channel RCAs. You'll also need a crossover filter, high-pass, to prevent bass notes tearing the tweeters apart.

  • Tracy Strout from fort Lupton co

    Posted on 8/11/2015 5:28:44 AM

    If your capacitors capable of enough farad, for both four channel amp and mono amp. Is it better/ok/or recommended to, split output of capacitor through a distribution block. Then to each individual amplifier. Simply making a Y connection from cap to amp's. All I ever see caps used for are sub/mono amp's. Never in line to a 4 channel amp why? .

  • Buck Pomerantz from Crutchfield

    Posted on 8/11/2015 1:02:12 PM

    Tracy, A capacitor provides a jolt of power to an electrical system when the demand exceeds the normal supply. As the typical subwoofer amplifier will be two or three times more powerful than the full-range amp in a system, that's where the greatest demand will occur, when the bass hits. You can certainly mount a capacitor as you describe, but I don't think it would be very effective. Mounting a cap on the sub amp's power cable as close to that amp as possible will provide the fastest deliver of power where it's most needed.

  • Junior Dearmon from Humble , Tx.

    Posted on 8/13/2015 1:06:02 AM

    I have a ct sounds 1400.1 amp and two dvc 4ohm 12" mtx subs 400 watts rms and I have them wired at 1ohm. Should I wire them seperately or keep them the way I have them

  • Buck Pomerantz from Crutchfield

    Posted on 8/13/2015 1:20:35 PM

    Junior, That amplifier can apparently put out 1400 watts RMS at 1 ohm, which may be a bit much for those two 400 watts RMS rated subs (800 watts together), but you should be okay if you keep the amp's gain set low.

  • will from Newcastle

    Posted on 8/15/2015 6:57:23 AM

    Hi guys On the back of my head unit, i have RCA outputs for left and right speakers how do i connect these to my amp as it only has left and right inputs

  • Buck Pomerantz from Crutchfield

    Posted on 8/17/2015 10:21:09 AM

    Will, If you're using your amplifier to drive front speakers in your car, you should plug one end of a 2-channel RCA cable into the Front Left and Front Right output channels of the receiver and the other end into your amp's inputs. If you're using the amp for a subwoofer, use the rear channels of the receiver and go through the receiver's menu to see if there are subwoofer settings you need to adjust.

  • Seth from Fort Lauderdale, FL

    Posted on 8/20/2015 12:00:46 PM

    The remote turn-on lead in the diagram shows it being split from the receiver and going to two amps. Is this actually how it should be done? I've read elsewhere that a relay should be used for turning on multiple amps... I'm about to begin an install and just want to make sure it's done right.

  • Buck Pomerantz from Crutchfield

    Posted on 8/20/2015 12:59:58 PM

    Seth, The turn-on lead in the diagram is shown split like that for clarity. Usually, you daisy-chain the turn-on lead from one amp to another: from the receiver to the first amp, then on to the second. A receiver's turn-on circuit can usually handle up to two or three amps before it becomes overwhelmed. Any more than that would require a relay to provide enough 12-volt current to work.

  • larry olson from crozet

    Posted on 8/27/2015 9:41:51 AM

    I'm trying to hook up a fm car radio in my work shop. If I buy a 12volt ACDC PLUG, does it matter how many amps I should get. I'm just putting the basic speakers with it. I know radios come with different amps.

  • Buck Pomerantz from Crutchfield

    Posted on 8/27/2015 11:10:52 AM

    Larry, When playing music at top volume, a typical car radio will draw up to 9 amperes of current during the loudest musical peaks. For gentler listening, it would be more like 3 amperes. If you're only hooking up two speakers, even less. However, you will find that the cost of such a 12-volt DC power supply exceeds the cost of a decent home radio.

  • Carl from Raceland

    Posted on 8/31/2015 4:30:11 PM

    Can someone tell me if it can be done, how to wire up a Pyle 4000 watt 4 Channel Bridgeable MOSFET Amplifier to one BOSS 2000 watt 4 ohm sub and one Lanzar 1200 watt 6"X 9" 8 ohm full range speaker.

  • Buck Pomerantz from Crutchfield

    Posted on 9/1/2015 11:49:18 AM

    Carl, Yes, you can connect that subwoofer to two bridged channels of that amp and that speaker to the other two channels bridged together. Set the amp's input mode to 2-channel.

  • Nick from Tacoma, WA

    Posted on 9/2/2015 7:16:30 PM

    Hi. I'm planning on upgrading my wife's 2005 Camry. The idea is to upgrade the stock (non jbl) system to a Kenwood KDC-X998 deck with a pair of Pioneer TSD1602R 6.5" in the front, a similar pair that doesn't require too much (or any) modification in the rear deck, and a sub or 2 in the trunk. I was planning on powering all of these with a 5ch Kenwood KAC-7005PS. The 6.5's are rated at 60w rms/ 260w max ea. The amp puts out 40w rms x 4 @4 ohm or can be bridged to 3 channel to put out 100w rms to each of the fronts and still leave me plenty (up to 500w at 2 ohm) for a box in the trunk. My questions are: Would I be underpowering the (4) 6.5's at 40w ea? Would I be better of just disconnecting the stock rears altogether, bridging the front and rear channels and just running the 2 6.5's in the front at 100w ea. and sub(s) in the trunk, or would I then be overpowering the fronts? And finally, am I going about this all wrong, should I be looking at an entirely different setup altogether? My goal is more clean quality sound you can "feel" without breaking the bank, than deafening volume and bass that sets off every alarm for a 3 block radius. I'm also trying to stay away from modifications to the car as much as possible. I am confident in wiring everything g up myself, but I am by no means an installer and I don't want to end up hacking up my wife's interior. Thanks for the help. Any recommendations are welcomed and appreciated.

  • Buck Pomerantz from Crutchfield

    Posted on 9/3/2015 9:27:03 AM

    Nick, I think in a Camry, 40 watts per speaker and 500 for the subwoofer will prove to be a good balance. Try it and if you think the bass overpowers the mids and highs, then you can bridge the channels to run the front speakers.

  • Szekely

    Posted on 9/4/2015 1:34:35 AM

    Hi, I have an MFD1 system in mi vw jetta, which has only 4 outputs for the 4 speakers - no sub out. I am using a 4 channel amplifier for these, but I would like to add another amplifier and a subwoofer, too. The current amplifier (renegade ren 1100) has an output channel. Can I connect that to the input of the subwoofers amp? Thanks!

  • Buck Pomerantz from Crutchfield

    Posted on 9/4/2015 10:55:14 AM

    Szekely, Yes, that's exactly what that feature is for.

  • Craig from Vancouver

    Posted on 9/24/2015 3:05:17 AM

    First of all, thanks for all of the resources and information you guys provide. I'm a little confused about the factory wires that go to the speakers. If we run rca's from the head unit to the amp, and then we run speaker wire from the amp to the speakers... What happens to the factory wire that's installed in the factory speakers? And what's the point of wiring the factory speaker wires into the wiring harness for the head unit? I hope those questions are clear. Thanks again!

  • Buck Pomerantz from Crutchfield

    Posted on 9/24/2015 10:20:20 AM

    Craig, If you install new speaker wiring from your amp to your speakers: 1) You should disconnect the old factory wiring at each speaker and cut back and tape the wires so no conductor can make contact with metal. 2) You'll have no need of any speaker wiring from the harness and can cut those leads from both the vehicle and receiver harnesses.

  • Marcus Navarette from Lubbock

    Posted on 10/5/2015 11:54:45 PM

    Hello I need your help, I have a Honda Accord 2012 SE and I am going to install 4 new speakers and wanted to get the best bass possible without adding a sub. So I figured I would wire a 4 channel amp, or get a new head unit but my factory head unit does not have any connections on the back that I can use. And it is an odd head unit. Can you give me advice as to what I should do?

  • Buck Pomerantz from Crutchfield

    Posted on 10/6/2015 12:56:29 PM

    Marcus, I've forwarded your questions to Crutchfield's Sales Advisor Team, and a member will get in touch with you by email to offer suggestions and help you choose the right gear for you and your vehicle. For immediate help, you can contact them via phone or chat.

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