Choosing the Amp: What Amp Do I Need For My 2 12 Subs?

Amplifiers take weak signals and make them more powerful, drastically improving your subwoofers’ sound quality. If your speakers are underpowered, they’re likely not working to their maximum potential, leading to poor sound output and overall quality. Most factory-installed car stereos provide little power output to drive your subs, so an amplifier is necessary. So, you may wonder, what amp do I need for my 2 12 subs? When choosing amps for 12-inch subs, don’t go by “peak,” go by root mean square (RMS). The ideal is 400 watts RMS per subwoofer, leading to 800 watts for two 12″ subs, which means you’ll need amplifiers with at least 1200 watts.

Keep in mind that when choosing an amplifier, the most crucial thing is to pick one with the right amount of power for your subwoofers. After deciding how much power you need, determine which type of amplifier to use. All in all, having an adequately matched amplifier and speaker combination will produce a full and rich sound with overall more power, allowing you to hear all the nuances of the media you’re listening to.

Building the System: How to Match Amp to Sub

To get the most out of your car audio system and the best bass sounds, you need to learn how to match the amp to the sub. Consider these combinations to find the proper amplifier:

  • One Single 4 ohms Voice Coil Sub

One single voice coil subwoofer with 4 ohms is ideally suited to a 2-channel amp, giving you more power and relatively cheaper by bridging the amp’s output.

  • One 4 ohms Dual Voice Coil Sub

With two voice coils, dual voice coil (DVC) subs offer car owners several ways of connecting them. It is also designed for better performance and heavy-duty power handling. A single DVC with 4 ohms is well suited for a mono-sub because they’re built to provide significant power at a lower impedance load. You’ll still get the maximum capacity when you wire the voice coils in a parallel connection, even if you only have a 2 ohms impedance.

  • Two 4 ohms Single Voice Coil Subs

Car owners can have their car stereo installation move lots of energy through the air with this combination. When wiring two subs in parallel, you present a 2 ohms impedance. The perfect match for this is the mono sub amp, giving you the most output even when you connect the subs at 2 ohms.

  • Two 4 ohms Dual Voice Coil Subs

Two 4 ohms DVC subs offer excellent wiring flexibility to acquire the bass you want. A 2-channel amplifier is the best for this combo. When you wire the subwoofers with a bridged 2-channel amp, the total impedance will be 4 ohms.

How Many Watts Do 2 12 Kickers Need?

Subwoofers typically have two power handling requirements, including root means square (RMS) watts, which refer to the continuous power handling capability, and the peak watts of peak power handling. The subwoofer’s RMS rating indicates the power or amount of energy it can typically handle. At the same time, the peak or maximum energy specifies the maximum amount the sub can operate without causing any damage. For the best sound quality, the RMS watts must match the amps, and for 12’s, around 1000 watts should do — specifically, 1200-watt amplifiers are your best choice.

Matching the Amp to the RMS Range

Today, most power amps indicate the RMS range in watts, showing the minimum and maximum power that the amp can produce. After determining the amp’s capability, use the numbers to compare with the RMS wattage range. The amp must deliver between 75% minimum and 150% maximum of the RMS wattage range. Calculate the RMS rating of your subwoofers and multiply the result with the number of subwoofers, which should give the total RMS rating for the two subs.

Overpowered subwoofers are a better choice than unpowered ones. For every subwoofer you want to add to your car audio system, you also need to upgrade the amp to reflect the additional sub’s RMS watts — giving you overall better performance.

How Do I Know What Power Amps to Get for My Subs?

When choosing amps, the most crucial thing to look for is the amount of power needed for your subwoofers. After settling on an amount, you can go ahead and look for the best amplifier for your subs. There are two “main” amp styles for mast bass systems, including mono or single-channel amps and 2-channel amps. Car stereo amplifiers range from one to six channels. However, single-channel amplifiers, in general, are the best for producing quality bass sound.

Single-channel amps can process single audio signals using a single channel wired to the subwoofer, and they’re the best choice for powering subs since they can produce max power with low impedance. Keep in mind that you can wire multiple subs to a single channel amp, and each one will have the same frequency. Pick one that can put out power in the “total” RMS wattage range, based on their wiring.

If you’re planning on adding various subwoofers to your car’s sound system, consider upgrading the power amplifier too. After finding an amp that matches your car’s subwoofer RMS watt and impedance, connect the two and wire them into the vehicle’s stereo system, giving your car subsystem better power handling and overall sound.

How Much Power Do I Need for 2 Subs?

Two subs wired together need to be the same coil type and impedance because if they’re not, the power won’t divide evenly between them. Some subwoofers would be overpowered while others aren’t. If you’re looking to run different subs in your system, each one will need a separate amplifier.

Steps to Match Amplifier to Subwoofer for Proper Power Handling

Here’s how to know what amplifier you need for your subwoofer:

  • Find out the watts RMS ratings

After finding the watts RMS rating of your subwoofers, multiply the two subs by the RMS rating of each one, helping you get the total RMS rating. Make sure the amplifiers you pick will supply no more than the total rating.

  • Figure the total impedance

Impedance is the result of combining coils and subs. Generally, a single voice coil (SVC) has one pair of terminals, while a dual voice coil (DVC) has two. For example, if you have one SVC with 2 ohms, you only have 2 ohms of impedance. Meanwhile, one DVC with 2 ohms has 1 ohm or 4 ohms of impedance.

  • Choose one that can do both.

Look for amplifiers that can put out maximum power up to the RMS wattage of your car subwoofer and impedance load. Regardless if it’s 2 ohms or more.

Does it Work? The Subwoofer and Amp Matcher

It’s no secret that having a subwoofer is a great addition to improve the sound of your car audio system, providing more fullness to music and producing rich and more profound notes that any music lover would appreciate. However, to get the maximum potential for your woofer and help it sound great, you’ll need to pair it with the “right amp.” A subwoofer and amp matcher will make a massive difference in the sub’s power and overall audio quality, ensuring your car stereo system is working correctly.

Matching Works

Matching these two car stereo components works. Established manufacturers like Rockford Fosgate make sure that the system’s specs matches straight out of the factory. Rockford Fosgate has been manufacturing vehicle sound systems since 1973.

However, you’ll need to find an amplifier that perfectly matches your sub. In other words, you need to ensure the amp’s power is capable of meeting the sub’s specifications. It helps them work properly together on a “regular basis,” producing quality bass. For the best audio results, make sure the watts RMS of the subwoofer and amplifier match. However, generally, as long as you buy a quality speaker and pair it with a decent amplifier, you’re bound to get quality audio results from your car’s speakers.

After all, modern car speakers are forgiving, and most are well-built. Just make sure they have capable and matching impedance and wattage.

Additional Considerations on How to Safely Match Amp to Sub

Besides pairing the right amp with the right subwoofer, you need to consider the safety of the pairing when you match the amp to sub. However, when you ask audio experts how much amplification car speakers need, given their power handling rating — expect different opinions. Generally, there are two common causes of a blown speaker that car owners should avoid at all costs. First is connecting an amplifier to a sub with a continuous power rating, and secondly, running ones that are far too weak for the speakers connected.

To avoid these scenarios and keep your car speaker, sub, and amplifier safe, take additional considerations. First, connecting your car speaker to an amplifier with a continuous power rating will lead to overheating since it can’t dissipate heat energy properly. Next is running amplifiers that are too weak for the speakers connected to it.

Although lower power isn’t “bad,” in general, it can damage the whole audio system when you keep cranking the volume knob to reach the listening level that doesn’t exist with weak input. Instead, your amplifiers will start burning themselves since you’re demanding more energy than they can handle. This situation will cause the components to overheat and clip the signal sent to the speakers, creating distortion. If the amp is enough to meet the subwoofer’s requirements, then upgrade to a hefty size amp.

The Top Picks: What’s the Best Amp For 2 12 Subs

Amplifiers also come in different types of classes, where the letters serve as a reference on how efficient their wave functionality is. So, what’s the best amp for 2 12 subs? All amps conduct through waveforms, and here are the different classes to help you find the best amp for you:

  • A Class

An A-class amp conducts throughout 360 degrees of a waveform, meaning that they’re less likely to have background hums because of their single-ended design. Class A amplifiers require high-level current flowing continually, giving your car subwoofers quality audio. However, it needs to run continuously, which wastes a lot of energy load.

  • B Class

A B-class amp has similar functions to the A-class above, but it ensures that only half the devices are working, with each one covering a 180-degree portion. It’s generally more efficient and has less wastage. However, it creates a delay between the two amplifiers.

  • D Class

A D-class amp is the most efficient available, making them the best among the amplifier classes. That’s because they rapidly fluctuate the devices connected between an on or off state, allowing car owners to optimize their power consumption. However, they are the most expensive ones, so consider your budget.

What is a Good Amp for a Dual Voice Coil 12-inch Sub?

To find a good “amplifier” for a 12-inch sub, don’t forget to consider the following factors:

  • Impedance

Impedance is used in amp and woofer spec sheets. It’s the measure of electrical resistance of your stereo components, and impedance is measured in ohms. Generally, impedance is part of the equation in determining the synergy between these components. A typical speaker carries ratings between 4 ohms and 8 ohms. Meanwhile, amplifiers operate efficiently in a “specified” range, ranging from anywhere between 2 ohms to 16 ohms. It’s best to check your specifications. However, connecting a woofer rated around 2 ohms, 4 ohms, or 18 ohms is all right when that’s the case. For more than two speakers you have to determine the total impedance of the system.

Generally, connecting higher impedance speakers is fine. However, it’s best to avoid plugging low impedance speakers — for instance, 2 ohms into an amplifier specifying a minimum limit of 8 ohms.

  • Sensitivity

Sensitivity refers to how loud subs will be in decibels from one meter away when driven by one watt. It generally relates to how loud your woofers can get. When distance and power are the same, a lower sensitivity sub would sound quieter than those who are more sensitive, around 88dB in the same area and setup. Although this doesn’t make or break a good sub, it saves you from buying more expensive ones.


When you’re prepared to add subs and a bass system to your car, you have many options to choose from, and after getting past the “basic” question of the size and number of subs you want, you’ll need to decide the type of amplifier you wish to use. Remember, when choosing the right amplifier, the most crucial thing to consider is picking one with the right amount of power to handle your woofers. After deciding how much you need, see what type you want to use.

We hope this article helped you learn more about matching subwoofers and amplifiers — giving you the best sound quality possible.