Dayton Audio is an American loudspeaker and audio component company based in Springboro, Ohio, which does most of its engineering in the US. Alongside finished speakers, soundbars and subwoofers, it sells the parts speakers are built from, including woofers, tweeters, planar and ribbon transducers, passive radiators and exciters that turn almost any surface into a speaker. Some of its woofers use its patented MMAG magnet design. DIY builders can buy crossovers, cabinets and complete speaker kits, along with measurement microphones and computer-based measurement tools to test the result.