The Kicker CompRT is a very good speaker, especially if you're working with a smaller space for your car's audio set-up. While it isn't always the case in recent times, getting a speaker with decent low-end frequencies usually means choosing one with serious depth to move the air around. As such, you can't fit them into smaller spaces. That's not the case with the Kicker CompRT series of speakers, which is why they place among the best car subwoofers. With half the mounting depth of most subs, you can install them in tight places where the average subwoofer wouldn't fit. A sealed enclosure only requires 0.5 cubic feet of space, while the ported enclosure requires 1.75 feet of space.
The low end that the CompRT subwoofers produce is booming, especially considering the mounting depth. The frequency response is slightly below average, with the 12-inch subwoofer and the 10-inch subwoofer reaching down to 25Hz. However, the high frequency reach of 500Hz means that it can boost the low-mid frequencies, where you hear much of the warmth in a guitar or male vocals, though doing this can also lead to a muddy mix.
While the Kicker CompRT is an older model now, you can still get it via Amazon and other retailers, and it's well worth picking up - especially if you can find one second hand or open-box.
The sensitivity rating is 87.1dB, which is slightly below average. This indicates how efficiently the subwoofer converts power to volume; using 1 watt of power, the subwoofer measured 87.1dB of volume output at 1 meter. For comparison, the Pioneer Champion and Infinity Reference, the two top subwoofers that we reviewed, both have a sensitivity of 96dB. Since every 3dB increase of a sensitivity rating requires half the power, the CompRT subwoofer would need 100 watts to produce the same output of a 96dB sub using only 12.5 watts. This doesn't mean you can't shake the rearview mirrors off the cars next to you; the speaker simply requires more power to do so.
With the below-average sensitivity, it's good that the CompRT subwoofer's power handling is among the best. With a continuous power handling of 800 watts, which is the highest among the car subwoofers we reviewed, you can easily reach dangerous volume levels. You don't have to worry about clipping the speakers either, because the peak power handling is 1,600 watts – the second-highest peak power-handling rating among the car subwoofers in our lineup. If you want your subwoofer to kick out your windows, you have the muscle to do so.
The Kicker CompRT subwoofers have a shallow-mount design that allows you to install them in smaller enclosures than the average subwoofer requires. The lack of depth doesn't sacrifice too much fullness, though, as the bass definitely booms with the high power-handling ratings. The power-handling peak makes up for its low sensitivity rating.