Founded in 1936 by Peter J. Walker, Quad is famous for pushing the boundaries of hi-fi design.

Quad was the first company to develop an electrostatic loudspeaker (ESL) for home use and theirs is considered by many industry experts and enthusiasts to be the most accurate speaker in the world, earning cult and iconic status in the annals of hi-fi.  Conventional speakers use multiple individual dynamic drivers to produce specific frequencies of sound as well as complex crossover circuits to divide up music signals to each of these individual drivers. This complex system causes smearing of sound. Quad's ESL technology avoids this problem entirely by using only one very lightweight Mylar film (thinner than a human hair!) and suspending it between two electrically charged metal grids, eliminating the need for heavy conventional drivers and crossovers.  This allows Quad ESL speakers to play with extreme precision and accuracy. With these advancements in speaker technology came a growing demand for more stable power amplifiers. To meet this need, Quad patented their "Current Dumping Technology" which ingeniously marries a high quality Class A amplifier with a high current Class B amplifier to produce a high performance amplifier that is stable into any speaker.

High-performance speakers and stable, high-power amplifiers are the trademarks of Quad, one of the finest manufacturers of hi-fi stereo equipment.