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Car amplifiers FAQ

Answers to common questions about car amplifiers

Our car amplifier FAQ answers many common questions about choosing and installing an amplifier. We cover questions about power and configuration, connecting speakers and subs, and amplifier installation.

Every day, our Sales Advisors and Tech Support Specialists answer a lot of questions about adding an amplifier to your stereo system. These mysterious electronic boxes are often confusing as to their features, functions, and appropriate applications. This article answers many of these common questions. Hopefully, it will help you understand car amplifiers better.

Be sure to also read our Car Amplifier Buying Guide to learn more about choosing the right amplifier. Now, on to the questions.

Power and configuration

» How many channels does my amplifier need to have? What are the options?

» Why is it best to use a mono 1-channel amp for my subwoofer system?

» What's "bridging" an amp, and can I do it with mine?

» What's a "high-current" amplifier? Or a "2-ohm" or a "one-ohm" amp?

» How much power should I get for my speakers?

» How much power should I get for my subwoofer?

» What are RMS and Peak power ratings?

» What's the most powerful amp I can hook up to my vehicle's factory electrical system?

» What're the differences between Class A, AB, and D amplifiers?

Speakers and subs

» Can I add an amp to power my vehicle's factory speakers?

» What are speaker and subwoofer "ohms of impedance" and what do they have to do with amplifiers?

» Can I power speakers and a sub with one amp?

» How can I wire my sub to be 2-ohms, in order to maximize my amp's performance?


» How do you install a car amplifier?

» Can I install an amplifier in my EV (all-electric vehicle)? How about in a hybrid gas-electric vehicle?

» Where can I mount my amp?

» What wiring do I need?

» What's "Ground" and why is that connection so important?

» Why do I need to install a separate fuse near the battery?

» In my amp wiring kit, what's the blue wire for?

» How do I power a multi-amp system?

» How do I wire an amplifier into my factory stereo system?

» How do I wire an amplifier to my aftermarket stereo system?

» What's amplifier "gain" and how should I set or adjust it?

» What're "high-pass and low-pass filters" and how should I set or adjust them? How about "bandpass" and "subsonic" filters?

» What's a "bass boost" and how should I set or adjust it?

» Why won't my amplifier turn on?

Call us for help and advice

» Can I call Crutchfield and talk to a real person for help and advice??

JBL Stage A6002 car amp on pale yellow background

JBL Stage A6002 two-channel amp can power two speakers with 60 watts RMS each, or a subwoofer with 140 watts RMS.

Questions about amplifier power and configuration

Planning your system is the key to getting the right gear. These are common questions about knowing what kind of amplifier you need. Be sure to also read our Car Amplifier Buying Guide for more details.

Q: How many channels does my amplifier need to have? What are the options?

A: Each channel of an amplifier is a discrete source of power, intended to drive one speaker, sub, or a component set that uses a passive crossover. How many channels you need depends on your plans for your audio system now and in the future.

A 2-channel amplifier will be the practical solution when you only need to power a single pair of speakers – for people who like their music with a strong front stage and don't even use rear speakers.

Most people choose to use a 4-channel amp because they like rear-fill sound in their car and want to retain front-to-rear fade control. Most 4-channel amps can also be used in 3-channel mode – two channels to drive a pair of speakers and the other two bridged together to run a sub. This also gives you the option for future expansion of your system. Later on, you could use the 4-channel amp to run four speakers and add a separate amp for the subwoofer.

Diagram os Subwoofer and speakers on a 4-channel amp

Powering a subwoofer and a pair of speakers with a 4-channel amp

A 3-channel amp can take care of a single pair of speakers plus a sub quite effectively without any further modifications.

You may want to consider a 5-channel amplifier that can power your entire system from one convenient and compact package. It has four channels for your speakers, plus a fifth, higher-powered channel for your subwoofer.

6-channel, 8-channel, and 12-channel amplifiers exist, often with digital signal processing features, to handle newer OEM "premium" systems that have similar numbers of speakers.

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Q: Why is it best to use a mono 1-channel amp for my subwoofer system?

A: Bass needs much more power than higher frequencies in order to sound full and encompassing (which is what we want). Mono, 1-channel amplifiers are designed to power subwoofers. They feature much higher output power than multi-channel amps, and have tone controls and sonic filters specifically made to help reproduce bass that sounds (and feels) great.

Most subwoofer amplifiers can power two or more subs at a time, due to their large amount of wattage and their capability of handling the different impedance loads. (See our subwoofer wiring diagrams for more information. Also our "Ohms of impedance" Q&A below.)

Subwoofer amps only have one channel because stereo (2-channel) bass doesn't really exist. Our brains are good at locating the apparent position of high- and mid-frequency noises, but not low-frequency sounds. As far as bass goes, there is no left and right. Most single-channel amps have two sets of speaker output terminals, wired together inside the amp, to make it eaiser to hook up two subs to the same amp.

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Q: What's "bridging" an amp, and can I do it with mine?

A: Bridging combines two of an amplifier's channels into one more powerful channel in order to get more power to a single speaker, usually a subwoofer. For example, a 2-channel amp that puts out 75 watts RMS per channel at 4 ohms may be able to put out as much as 200 watts RMS at 4 ohms into one channel when bridged. Another example might be using a 4-channel amp to drive your left and right speakers with two of its channels, while driving a sub with its other two channels bridged together, saving you the need to buy a separate subwoofer amp. For more information, see our article, "How to bridge a car amplifier."

car amplifier connected in bridges mode

Most amplifiers clearly show you how to bridge each channel

A limitation on bridging is that amps that can work with 2-ohm loads per channel in "stereo," non-bridged mode can only safely drive 4-ohm loads when bridged. When an amp tries to drive a load that's too low, it usually automatically protects itself and shuts down. And you can't bridge a mono subwoofer amplifier because it only has one channel.

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Q: What's a "high-current" amplifier? Or a "2-ohm" or a "one-ohm" amp?

A: An amplifier is considered high-current if it can handle a one-ohm load. Most amps cannot. (See the "Ohms of impedance" Q&A below.) The ones that can are usually "1-ohm capable" subwoofer amplifiers or "2-ohm stable when bridged" multi-channel amps. (See "Bridging" Q&A above.)

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Q: How much power should I get for my speakers?

A: This will depend on what speakers you have, or plan to get, and how loud you want them to play. Car amplifiers come in a few different ranges of power, depending on each manufacturer, to accommodate different applications and taste.

  1. 25 – 60 watts RMS per channel. To hear music clearly over traffic and wind noises. Maximum appropriate power for factory speakers.
  2. 65 – 80 watts RMS per channel. For aftermarket speakers. Music sounds full, with all details audible.
  3. 90 – 120 watts RMS per channel. For high-performance speakers and components to play loudly.
  4. 125 – up watts RMS per channel. For competition-level components and high volume music in a large vehicle.

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Q: How much power should I get for my subwoofer?

A: It takes more power to produce low-frequency bass than it does for the higher-frequency sounds, so your subwoofer needs a lot more wattage than the full-range speakers do in order for the bass to blend in well and sound musically balanced.

A good rule of thumb is to power a subwoofer with about ten times the amount of power that the full-range speakers get.

  • If you're using your car's factory stereo – 100 to 250 watts RMS of power for the bass will do nicely.
  • An aftermarket receiver – you might want 250 to 500 watts RMS of power for your sub.
  • Amplified speakers with around 50 to 75 watts RMS per channel – plan on 500 to 750 watts RMS for bass.
  • A 100 watts RMS or higher per channel system – you'll want at least 1,000 watts RMS for your sub.

To avoid damage, never connect an amplifier with a watts RMS output that's higher than the subwoofer's total RMS power input rating.

Kicker CXA1200.1T car amp on light blue background

Kicker CXA1200.1T: This 1,200 watts RMS subwoofer amp will play your bass loudly.

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Q: What are RMS and Peak power ratings?

A: RMS wattage (sometimes called "continuous wattage") is a measurement of power capacity used for comparing and matching components together. Peak wattage, often double the RMS value, is a description used by the marketing department of the amp's manufacturer to sell more amps. You should only use RMS ratings when designing systems and matching gear.

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Q: What's the most powerful amp I can hook up to my vehicle's factory electrical system?

A: Your car's alternator ampere rating will determine how powerful an amplifier you can install. You can find out what your vehicle's alternator rating is in its owners' manual specifications and printed or stamped on the housing of the alternator itself. There, you'll find three numbers labelled as "IL" (low-current – at idling speed), "IRA" (rated current), and "VTV" (voltage). Use the current-rated number (IRA) for your calculations. We’ve done all the math for the examples below, but you can figure that the maximum wattage your vehicle's electrical system can support is 11.7 times the alternator's current rating.


  • 60A alternator will support up to 702 watts RMS
  • 90A alternator will support up to 1,053 watts RMS
  • 120A alternator will support up to 1,404 watts RMS
  • 160A alternator will support up to 1,872 watts RMS

Warning: When your alternator is unable to meet the demands of the electrical system, your vehicle can experience anything from dimming headlights to catastrophic engine, brake, and steering failures. Car audio competitors often replace their vehicle's factory alternators with heavy-duty upgrades in order to accommodate the massive power demands of their loud sound systems. (Also, see our Q&A about electric vehicles, below.)

The science and math

Figured conservatively, the electrical current available for your aftermarket system will be 40% of the alternator’s total available amperage (IRA). This number divided by a duty cycle of 1/3 for bass-heavy music times 75% efficiency for a Class D amplifier times 13 volts when the car’s running will come to 11.7 times the alternator’s IRA. This number is the electrical system’s maximum supportable wattage for an aftermarket amplifier.

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Q: What're the differences between Class A, AB, and D amplifiers?

A: Amplifiers are divided into different classes defined by how their internal circuitry works. In the car audio world, most amplifiers are Class D, because of their high-efficiency operation and compact size-to-power ratio.

  • Class A amps are large, heavy, run hot, and are used in expensive high-fidelity home stereo systems and audio laboratories.
  • Class AB amps are smaller, lighter, run cooler, and are used in less-critically accurate but still good-fidelity systems.
  • Class D amplifiers can be smaller, run cooler, and in a more efficient manner than any other class of amp, with audio fidelity on a par with most of them.

For more details, check out: Which amplifier class is best?

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Alpine KTA-450 car amp held in hands

A compact Class D amp like an Alpine KTA-450 4-channel power pack — about the size of your hand — can fit almost anywhere in your car.

Questions about speakers and subwoofers

Here are a few common questions about connecting your speakers.

Q: Can I add an amp to power my vehicle's factory speakers?

A: If you like the tone of your factory speakers but just want more power and impact to the sound, you can add amplifiers to your system as long as you understand the limitations of such an option. Factory speakers can't take a lot of power — they're designed to play with "deck power," a receiver's 10 to 25 watts RMS per channel built-in amp, or a "premium" factory amplifier with no more than about 50 watts RMS per channel.

Crutchfield carries quite a few car amplifiers rated for 60 watts RMS and under that will work well with factory speakers. Another option is to add an amplifier with built-in digital signal processing (DSP) in order to improve the sound quality and fidelity of your music as well as its volume and emotional impact.

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Q: What are speaker and subwoofer "ohms of impedance" and what do they have to do with amplifiers?

A: Impedance, measured in ohms, describes the resistance to a flow of current. Amplifiers make speakers work by pushing voltage and current against the electrical resistance of the speakers' voice coils to produce cone movement, resulting in sound. The amplifier senses this resistance as a "load" on its output. The lower the speaker's impedance, the easier it is for the amp to drive it.

The way the physics and math work for this is that, for example, an amplifier that can send 100 watts through a 4-ohm speaker will be able to send up to twice that much power, 200 watts, through a 2-ohm speaker. Although there are featured exceptions (see "high-current amp" Q&A above), the minimum impedance load most car amplifiers can handle is 2 ohms on each channel or 4 ohms on bridged channels. For more information check out our article, Wiring Subwoofers — What's all this about Ohms?

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Q: Can I power speakers and a sub with one amp?

A: There are a few amplifier configurations that can take care of your car speakers and subwoofer at the same time. Refer to the Q&A about amplifier channels at the top of this article.

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AudioControl D-6.1200 car amp on beige background

AudioControl D-6.1200 six-channel amp with digital signal processing will take good care of your whole system.

Q: How can I wire my sub to be 2-ohms, in order to maximize my amp's performance?

A: You can't wire every subwoofer to have any particular impedance you want it to have. For instance, you can't change the impedance of a single voice coil (SVC) subwoofer — the 2-ohm model has 2 ohms of impedance, the 4-ohm model has 4 ohms. It's when your subwoofer system has a dual voice coil (DVC) sub or multiple subwoofers wired together that knowing what wiring options are possible becomes important.

  • One SVC 4-ohm sub can only be wired as a 4-ohm load
  • One SVC 2-ohm sub can only be wired as a 2-ohm load
  • Two SVC 4-ohm subs can be wired together as a 2-ohm or an 8-ohm load
  • Two SVC 2-ohm subs can be wired together as a 4-ohm or a 1-ohm load
  • One DVC 4-ohm sub can be wired as a 2-ohm or an 8-ohm load
  • One DVC 2-ohm sub can be wired as a 4-ohm or a 1-ohm load
  • Two DVC 4-ohm subs can be wired together as a 1-ohm, a 4-ohm, or a 16-ohm load.
  • Two DVC 2-ohm subs can be wired together as a 0.5-ohm, a 2-ohm, or an 8-ohm load.

Wiring solutions for three- and four-sub systems can get pretty complicated, so we won't go into those here. For specific wiring options and schematics, check out our Subwoofer wiring diagrams.

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Questions about amplifier installation

These are a lot of the common questions we get about installing and connecting an amplifier. For help with installation problems, be sure to read our guide to troubleshooting your amplifier installation.

Q: How do you install a car amplifier?

A: For detailed step-by-step instructions, see our Car amplifier installation guide. You can also check out our short video How to install a car amplifier.

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Q: Can I install an amplifier in my EV (all-electric vehicle)? How about in a hybrid gas-electric vehicle?

A: You should not install an aftermarket amplifier in an electric vehicle (EV). There is no reserve electric power available for any aftermarket accessories in these vehicles. Hybrid-electric vehicles have some flexibility, but you can't push them too far. Read our article about installing gear in hybrid vehicles for more information.

Some people get around this issue by installing a dedicated and isolated 12-volt DC power supply (i.e., a second battery) for the new amplifier to use without affecting the car's operation. This isolated second battery will need to be recharged separately from the vehicle's main battery as well.

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Car ampheld in hands wired up behind open car trunk

Rockford Fosgate Prime R2-500X1 mono sub amp wired for action, ready to mount.

Q: Where can I mount my amp?

A: An amplifier produces heat, which its heat sink absorbs and then dissipates into the air. Wherever you mount your amplifier, you need to leave a few inches of air space around each side so that it can stay as cool as possible, otherwise it may overheat and shut down. Also make sure there's enough room for you to connect the wiring and adjust the controls during installation and servicing.

Do not bolt or screw your amplifier directly to your car's metal chassis — that's inviting noise issues, like ground loops which hum or buzz. Most installers mount the amp on a wooden board or plastic panel and then attach that to the car body. Follow the manufacturer's recommendations for locating the amplifier and make sure it's mounted securely.

Since space is at a premium in most vehicles, two common locations are under a seat and in the trunk or hatch area. Under-seat mounting is space-efficient, keeps the amp hidden from view, and lets you run shorter cables to the receiver. A rear-mounted amp requires longer power and signal cables but makes it easier to get to the amp's controls.

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car amplifiers connected to wiring kit parts

Q: What wiring do I need?

A: Car amplifiers don't come with the wiring necessary to hook them up. The wiring you need will depend on your amp's power rating and how you're connecting it to the stereo. Luckily, we offer a wide selection of amp wiring kits and input and output signal wiring that can provide everything you need to connect your amp. See the Accessories tab for the amplifier you plan to buy (or already have) for a selection of the proper wiring kits and speaker wire. For more details, read our amplifier wiring kit buying guide.

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installing a ground wire for a car amp

Q: What's "Ground" and why is that connection so important?

A: The ground connection completes the system's power flow from the battery, through the amplifier, and back to the battery. The vehicle's metallic frame is the power supply's ground. That's what the negative terminal of the battery is directly connected to. Loose or badly located ground connections are responsible for more amp noise trouble than anything else, by far. Make sure your amplifier is grounded tightly to the chassis of your vehicle, with all the dirt and paint removed where contact is made.

Read our amplifier installation guide for more details.

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installing a fuse block with heavy gauge wire

Q: Why do I need to install a separate fuse near the battery?

A: You need to install a fuse at the battery to protect the power wiring, your car, and yourself against fire. In the event of an accident, you do not want a live wire stretching throughout your vehicle overheating, melting, and then igniting. For more information see our Car amplifier power wire fuses article.

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Q: In my amp wiring kit, what's the blue wire for?

A: The thin blue wire is the turn-on lead and it must be connected properly in order for your amplifier to power up. It carries a 12-volt DC signal from your stereo to your amp, triggering an electronic switch inside the amp that powers on the amp whenever the stereo turns on. In the case of a factory stereo with no remote connection, you can tie into a switched 12-volt source (one that only comes on when the car is running) in the fuse box.

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Q: How do I power a multi-amp system?

A: You have to supply power from the battery to every amp in your system. You do this by running a lower-gauge (thicker) power wire from the battery to a power distribution block near your amps. From the distribution block, you run smaller power wires to each amplifier. You do the same thing for the ground wires.

Our amplifier wiring kit buying guide covers this in more detail.

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Q: How do I wire an amplifier into my factory stereo system?

A: In addition to running power, ground, and a remote turn-on lead, your amp hook-up will require input and output wiring.

  • Most late 20th century factory car radios have analog outputs, and you can connect the speaker wires coming from the radio's outputs directly to an amplifier that features speaker-level inputs. Or you can use a line output converter to ensure that the amp can handle the factory signal. The amp's outputs can then connect to the factory speaker wiring at the same location behind the radio.
  • Cars today have amplified digital factory systems that make adding an aftermarket amplifier more difficult. The best way to install an amplifier while retaining your vehicle's factory audio features, like hands-free calling and controllable warning-chime volume, is to use a vehicle-specific amplifier replacement module and wiring harness.

See our article "Adding an amplifier to a premium factory system" for more information.

Pioneer GM-DX874 car amp on beige background

The Pioneer GM-DX874 four-channel amp comes with input adapters and a remote bass knob.

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Q: How do I wire an amplifier to my aftermarket stereo system?

A: Normally you use RCA patch cables to send the signal from your receiver to your amplifiers. Presumably, the receiver will already be installed with the interface wiring necessary for all the factory audio functions to operate connected correctly. Most receivers have three sets of preamp outputs to provide signal for your front speakers, rear speakers, and subwoofer amp channels. You may have to use Y-adapters to provide signal for a multi-amp setup, or use amps with built-in preamp outputs that allow you to daisy chain the signal from one amp to the next. You then send the amps' output signals back through the factory speaker wiring harness or run new speaker wires throughout your vehicle.

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Q: What's amplifier "gain" and how should I set or adjust it?

A: A car amplifier's gain control adjusts its input sensitivity to match the output level of the receiver or other source unit it's connected to. This is done so that the signal the amp works with isn't so weak that we hear the system's ambient background noise, nor is it so strong that the signal "clips" and the sound distorts.

You can think of this essential amp setup procedure like it's a "Goldilocks" adjustment so your system won't sound too loud, won't sound too soft; but will sound just right.

To set amp gain, first you play a familiar piece of music, then turn the gain up until the music sounds distorted. Then turn it back down until the music sounds clean. For more details about setting amplifier gain see How to set amplifier gain using test tones.

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Q: What're "high-pass and low-pass filters" and how should I set or adjust them? How about "bandpass" and "subsonic" filters?

A: In car audio, electronic crossover filters — high-pass, low-pass, bandpass, and subsonic filters — divide full-range input signals into discrete frequency-limited ranges or bands of sound so each of the different kinds of speakers can play just what they were designed to handle and deliver clean output without distorting — tweeters playing high frequencies only, subwoofers low bass, etc.

  • A high-pass filter — sometimes referred to as a "low-cut" filter — removes the notes below the filter's frequency setting so tweeters and midrange drivers won't try to play bass notes that they weren't designed to play without distorting.
  • A low-pass, or "high-cut," filter removes the notes above the filter's frequency setting so mid-bass woofers and subwoofers won't try to play high notes that they weren't designed to play without distorting or muddying the pure bass tones.
  • A bandpass filter employs both high-pass and low-pass filters so midrange speakers can play cleanly with the very high and very low notes kept away.
  • A subsonic filter, sometimes called an infrasonic filter, is used to remove the extremely low bass notes (often below the range of human hearing) that the amplifier would otherwise waste energy trying to reproduce. Subsonic filters are also used with ported subwoofer enclosures to reduce the unwanted loud booming notes around the box's resonant frequency.

An easy way to set up high- and low-pass crossover filters is to start with an approximation, setting both filters at 100 Hz., and then fine-tune by ear.

  1. You play a favorite, well-known song or test track. With the sub turned off, you adjust the high-pass control so no low-frequency bass sounds play through your midrange speakers and tweeters.
  2. Then, with the "full-range" speakers turned down or off and the subwoofer turned back on, you listen to the music coming out of your sub alone and slowly adjust the low-pass filter until all the high- and mid-frequency notes disappear. The low-pass filter lets you filter out the cymbals, strings, vocals, and guitars while keeping the bass guitar, synths, low tom-toms, and kick drums.
  3. With all the speakers and subs playing, you can tweak the controls the small amounts needed to smooth out any high and low bumps in the sound.

Crossover filters control the amounts of power going to different elements in a sound system — they should not be used as tone controls. That's the job of an equalizer or sound processor.

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Q: What's a "bass boost" and how should I set or adjust it?

A: An amplifier's bass boost is a tone control that increases the volume of the bass notes, usually around 42 Hz., a popular bass drum tuning as well as the bass guitar's and piano's low E. To adjust a bass boost, slowly turn it up and listen to the bass beat. Applying just a little boost will bring up the kick a lot. Be careful with any boosting — this is where distortion is often introduced into a system. When you add bass to the signal, you'll need to readjust the amp's gain downward to prevent distortion.

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Q: Why won't my amplifier turn on?

A: The most common problems are:

  • Bad ground connection – this is the most common cause.
  • A missing fuse – either on the amp or on the power wire at the battery.
  • The remote turn-on lead isn't connected properly or it doesn't have enough power available for multiple amps in the system.

For more, see Troubleshooting your car amplifier installation.

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JL Audio RD900/5 car amp on a dramatic black surface

JL Audio RD900/5 five-channel amp has all the connections and controls necessary for great sound.

Q: Can I call Crutchfield and talk to a real person for help and advice?

A: Yes, you can.

For help choosing the perfect gear for your system, Crutchfield advisors are available via phone or chat. They will help guide you through the maze of product and accessory options and reach your goal of getting a great-sounding car audio system.

After receiving your new amplifier, or any product from Crutchfield, you can call Crutchfield tech support if you need help solving any issues you encounter with your new audio gear setup.

  • Tylar Bisnett

    Posted on 2/23/2024

    i am thinking about purchasing a rockford fosgate punch p1-2x10 loaded, vented enclosure, powered by a rockford fosgate r2-500x1 prime 500-watt mono amplifier with a rockford rfk4x 4 awg complete amplifier install kit. all of this will be going in my 2019 bmw 430i gran coupe which has the base factory stereo. i am looking to add more punch and clean, low-end bass to my sound system. do you think these will do the job?

    Commenter image

    Buck Pomerantz from Crutchfield

    on 2/24/2024

    Tyler, If you really are considering purchasing products, give us a call - and please stop posting comments on articles that have nothing to do with what you're looking for.
  • Brandon

    Posted on 4/15/2023

    Does a powered sub get enough air underneath the seat? I was thinking about powered subs but wondered about airflow or lack thereof

    Commenter image

    Buck Pomerantz from Crutchfield

    on 4/18/2023

    Brandon, Many compact powered subwoofers are made to fit and work well mounted under a seat. Give us a call, so an Advisor can help you get the sub that'll work best in your vehicle.
  • Matt from Hayti Missouri

    Posted on 3/3/2023

    Hello Sir, if you would please help me out on my car's three aftermarket amps I plan on installing, I'd be very appreciative of it... I had to install a factory radio DSP to install the amps, aftermarket speakers and subs. One of my amps has 1 pair of preamp outputs(JL Audio AB 2 channel A2150). My DSP only has 6 outputs and I need 8 since I'm running the 2 channel on my tweeters, along with four mids in front doors and rear deck(a pair in front/Pair in back), with a 4 channel amp on them. Then, two subs and a monoblock. My question is, can I run my DSP's outputs to my four channel and two channel amps then use my two channel's preamp outputs to connect my monoblock amp?? Thanks in advance!

    Commenter image

    Buck Pomerantz from Crutchfield

    on 3/3/2023

    Matt, Yes - that's exactly what those preamp outputs are for.
  • Ahmed Abualzain from Duhail

    Posted on 2/19/2023

    I need advice I have Boss BE7ACP-CFT receiver 2 rear Kicker 46CSC6934 2 front Kicker 46CSC54 1 subwo Kicker 44CWCD104 Which amp is the one for my setup? btw my car is BMW E30 1988

    Commenter image

    Buck Pomerantz from Crutchfield

    on 2/20/2023

    Ahmed, I don't know what's available in your country, but it sounds like you may like a 5-channel amp. There must be a car audio dealer somewhere in your part of the world that can help you.
  • Matthew from Peregian Springs

    Posted on 10/21/2022

    Hi, I am fitting Alpine R-S65.2 R-Series 6-1/2" Coaxial (100w rms) speakers in the rear and KICKER CSC54 5.25" 2-WAY COAXIAL SPEAKERS (75w rms) in the front of my original 60 series landcruiser Toyota. It has the factory head unit, which I won't be using or replacing, just leaving in place. I want to use the JL Audio Weatherproof Bluetooth Receiver -MBT-RX with my phone as a head unit, or to supply the music. I like the Kicker KEY200.4 Smart 4-Ch. Amplifier (auto-EQ/processor) 200 Watts Of Power (50x4) Because I can fit it behind the dash and have everything look factory. I'm not sure if this setup will work? Otherwise I'm possibly thinking of the Pioneer GM-D8704 Class FD 4-Channel Bridgeable Amplifier (100W RMS x 4) and putting it under the front seat. Would both these amp configurations work? Thank you.

    Commenter image

    Buck Pomerantz from Crutchfield

    on 10/21/2022

    Matthew, With questions like that, it's always better to have a conversation with a real live human. Give us a call and talk to one of our Advisors. We can help you choose the right gear and give you the right advice on how to install it.
  • Bill Richards from Salinas

    Posted on 9/12/2022

    Just purchased JBL Club 605CSQ component speaker system and 4 channel Soundstream reserve RSM4 1220d amp. Using the factory receiver still for a 2017 Ram Pro master van. Question can I use factory speaker lines with AMP ? My plan is to cut factory speaker wire behind receiver and tap speaker output to amps input. then send amp outputs back to stereo harness, and on to the speakers through factory wiring. My crossover. This way i shouldn't need the turn on lead wire since amp has speaker level inputs. hopefully this is correct. one other question is do i need to get 5-watt load resistors to keep factory radio working when speakers disconnected. Thanks, Bill

    Commenter image

    Buck Pomerantz from Crutchfield

    on 9/14/2022

    Bill, You can indeed hook up an amplifier to a factory stereo. Check out Connecting an amp to a factory stereo for more details about how to do it. If your amplifier can't handle the factory stereo's signal, due to power or impedance mismatching, then you'll need some sort of line output converter (LOC) or interface device. See Adding an amp for help with that.
  • max mcallister

    Posted on 7/31/2022

    can i run a 2 ohm and a 4 ohm speaker on a 2 Chanel 2 ohm amp?

    Commenter image

    Buck Pomerantz from Crutchfield

    on 8/1/2022

    Max, I'm reluctant to answer such theoretical questions because I have no way of knowing if the subs are DVC or SVC, or if they have different or the same power ratings. Without knowing precisely what amp and subs you're referring to, we can't help you with advice. If you want a question answered about a system, you must identify the gear by brand names and model numbers so we can get the right information to you.
  • Jeremy Hollier from Carencro

    Posted on 2/5/2022

    I have a p300-12 fosgate sub/amp combo and was wondering what is the optimal setting for the bass boost and crossover. Some are saying center the bass boost and run at around 80hz on crossover. Any thoughts?

    Commenter image

    Buck Pomerantz from Crutchfield

    on 2/7/2022

    Jeremy, There is no one optimum setting for bass - only the ones that sound good to you in your vehicle. Check out Tuning your subs for some guidance.
  • jaithish john from kuching

    Posted on 12/8/2021

    Dear Sir, I have a factory installed radio unit on my old Toyota that has the following specifications: PRODUCT ID: 12891 TOYOTA PART No.: PZ071-00018 F-TEN PRODUCT No: 123001-18100151 [AUDIO AMPLIFIER] Power output: 17.5W per channel into 4 ohms, Max. 40W X 4 I intend to add an amplifier , Blaupunkt VD502 whose specifications are as such : Channels : 2 /1 Max power 4 ohms : 2x100 / 1x300 watts Max Power 2 ohms : 2x200 watts RMS Power 4 ohms : 2x50 / 1x150 watts (THD @ < 0.07 %) RMS Power 2 ohms : 2x80 watts (THD @ < 0.07 %). The alternator output of my vehicle is rated at 12-14.8V , 80A. Will the amplifier addition affect the alternator? Also what will the capasitance value that would be required? Thanks

    Commenter image

    Buck Pomerantz from Crutchfield

    on 12/8/2021

    Jaithish, Your vehicle's electrical system should support that amplifier just fine, with no capacitor needed.
  • angelx from nicosia

    Posted on 7/29/2021

    Can u connect 6 coaxial speakers on 4 channel amp and still get the full potential of all 6 speakers like when u do with 4 speakers on 4 channel.?

    Commenter image

    Buck Pomerantz from Crutchfield

    on 7/31/2021

    Angelx, You can drive six speakers with four amplifier channels. Two speakers would be wired directly to two channels, and the other four speakers could be wired together in parallel - positive to positive, negative to negative - and driven by the other two amp channels. The amp would see the paired speakers as a 2-ohm load and send them about twice what each of the other speakers would get, but divided into the two speakers - it ends up each getting the same as the others.

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