• Do Subwoofers for Cars Differ from Home Stereo Subs

    Subwoofers for cars are nearly identical to those built for home stereos, with only a few differences. Subwoofers are speakers that play the lowest frequencies, also called bass, which regular speakers don’t play due to a crossover circuit that delivers the low frequencies. Most subwoofers (active) are self-powered, with a built-in amplifier and separate power source from the other equipment, which is how it has enough power to provide the low-frequency audio waves; passive subwoofers are powered by an external amplifier. It is typically built within a wood car subwoofer enclosure. A home subwoofer will be connected to a receiver or preamplifier.

    House subwoofers have better current, to drive stronger bass; cars don’t have enough power to supply the home versions. Car systems run off of 12v DC and 2 to 4 ohm impedance, while home stereos run off of 120v AC and 4 to 8 ohms. If you convert your car subwoofer to run in your home, note that it will only be effective in a small space like a small bedroom, since it’s built to be used in a small area like a car. Actually, though, the smallest subwoofers may be home theater subwoofers that are designed for smaller areas.

    A home theater subwoofer has more consistent current, while a car subwoofer’s current fluctuates, based on the car’s actions: revving the engine, for example, affects the subwoofer. There is not enough distance in a car to use typical home stereo subwoofers, which require up to 30 feet for proper reverberation; that’s why there’s more bass in your car stereo–it is bouncing off much shorter spaces. Car stereo equipment can have up to 3 to 5 times more harmonic distortion than home theater systems. Also note that car subs are unshielded, so anything magnetic like a computer hard drive may be affected by being near it.