Quad
Quad Hi-Fi is a manufacturer of high fidelity equipment, established by Peter J. Walker in the year 1936 in Huntingdon, Cambridgeshire, England. They produce sound equipment like valve amplifiers, electrostatic speakers, standard speakers, and headphones. Over the years, they have brought forth various equipment series, for instance - S-Series, Z-Series, Artera Series, and Vena Series. The company now offers a three-year warranty on its products.