THD Electronics
THD Electronics, Ltd. is a manufacturer of amplifier accessories, and a former manufacturer of vacuum-tube guitar amplifiers. It is located in Seattle, Washington. It was founded in 1986 by President and CEO Andrew Marshall. At one time specializing in hand-built, vacuum tube “boutique”-style amplifiers, it continues to manufacture the “world’s best selling [guitar amplifier] power attenuator,” the THD Hot Plate. The company is well known in the boutique amplifier market, and is often credited with the creation of this market in the United States. THD's line of products stayed relatively small despite its 22-year history as a company. Of its amplifiers, THD made three: the UniValve, BiValve-30, and Flexi-50. Name origins Copyright issues prevented Marshall from naming THD Electronics after himself, as Marshall Amplification had been established in the 1960s. Marshall also decided against naming the company after his first name because, in his words, “Who…is going to spend $2,500 on an ‘Andy Amp?’" Instead he chose THD, the acronym for “Total harmonic distortion”. '(Total harmonic distortion) is one of the ways that amplifiers are rated,' says Marshall. 'And in the hi-fi world, where people are quite conscious of total harmonic distortion, everybody goes for the lowest possible amount of