Electro-Harmonix (EHX) is a New York City-based company founded by Mike Matthews in 1968, known for electronic audio processors and rebranded vacuum tubes. It gained prominence in the mid-1970s for affordable guitar effects pedals, creating innovations like the Electric Mistress flanger, Memory Man analog delay, Micro Synthesizer, and Hot Tubes distortion simulator. In 1980, it also launched one of the first digital delay/looper pedals.