Sunfire SDS-10 Subwoofer


The Design

If you bought this subwoofer, took it home, plugged it in, and started using it, you might not ever realize that it has a passive radiator on the bottom. A passive radiator is like a normal speaker driver, but no magnet. Just the cone, rubber surround, spider, and frame.

A speaker with a passive radiator is somewhere between a ported speaker and a sealed enclosure. It does similar things as a port does, but it does it more in an active way. There will be a frequency where the active driver on the front doesn't seem to be moving at all, and the passive radiator is going like crazy. In fact, I didn't even realize it had a passive radiator until I was moving it around the lab, because I wasn't expecting one at this price point. But thar' she blows.


The rear panel has the On/Off toggle, Volume Control, Phase Control, and Low-Pass Crossover setting. Inputs and outputs are line-level RCA. The outputs are high-passed. You can set the power to turn on when it senses a signal or just leave it on all the time. The AC socket is more like one sees with CD players. It is non-grounded.