No car audio system is complete without a subwoofer to fulfill your bass needs. Subwoofers produce low frequency sounds ranging from 20-200 hz. Installing this separate speaker will compensate for the absent bass notes in your car audio. The result is a full listening experience that emulates the original recording quality from the studio. 

At the most basic level, subwoofers are just air pumps tasked with the job of moving air to produce low frequency sound. To make sound the subwoofer uses drivers which compress the air in the speaker box in a pulsating motion. The downside of subwoofers and their drivers is that these components are absolutely non-electric by default. As such, they require an adequate source of power from an amplifier to enable the flow of air producing sound.

The challenge comes in matching your subwoofer with an appropriate amplifier – not every amp is capable of powering each and every sub. Subwoofers vary in dimensions and capability. Each type of sub will need a specific amplifier with a power output that matches the power requirements of the subwoofer. 

This is why matching amplifiers and subwoofers can be perplexing. You can’t pick any old amp off the shelf and expect it to be a match made in heaven. Fortunately, Sonic Electronix has broken down everything you need to know about how to match subwoofers and amplifiers. 

There are three attributes to consider: Impedance, Channels and RMS Wattage.


This could very well be the most important factor to consider when matching an amplifier to a subwoofer. Impedance is the measure of precise electrical resistance. In simple terms, matching impedance with an amplifier is a lot like fitting your sink faucet with a water pipe. Get it even a bit wrong and the water may leak or lose pressure.

As far as subs and amps, getting the impedance wrong will result in overheating and horrible audio production. Labeled as Ohms, the speaker should have a higher capability than the amplifier. Depending on how the speakers’ voice coils are wired together will effect the Ohm rating.


Since you are already in the market for an amplifier, it’s worth noting that single-channel (mono amplifiers) are typically the best. This is because they process single audio signals that use one wired channel to the subwoofer to generate a powerful, dominant bass. 

Some people choose to wire a couple of great subwoofers to a mono channel. However, each sub will receive the same single frequency. 

It’s worth mentioning that low frequency sounds tend to avoid the creation of impact stereophonically, like their higher frequency counterparts. Therefore, all you require to get the job done is one channel.

RMS Wattage

Generally, subwoofers incorporate two power handling specifications. Also referred to as continuous power handling and peak watts or peak power.

RMS simply stands for the Root Mean Square wattage. The RMS wattage of your Subwoofer represents the amount or level of power that it can handle on a regular basis. The peak wattage specifically states the maximum power levels that the subwoofer can take for a brief period but will result in the unit being damaged. 

Peak is not the appropriate watts to base your decision off of. The sub won’t last and you will be replacing this product frequently; adhering to RMS will ensure a long product life. 

If you are looking to match an amplifier with a subwoofer and want the best sound quality, make sure you match the RMS wattage on both. Currently, many of the amplifiers in the market mention a range of RMS watts that specifies the maximum and minimum power range. Once you know the range your intended amp can produce, you’ll need to make sure that the amp is able to conduct 75 to 150 percent of the subs RMS rating.

Combining an amplifier and subwoofer will get the most out of your car’s audio system. Matching all the above elements will guarantee superb sound. The process sounds a lot more difficult than it is. Both the sub and the amp will give you the impedance, channels and RMS wattage on the box; all you have to do is appropriately pair the two! To simplify this process, you can buy complete subwoofer and amplifier sets.