Esoteric Audio Research is a British high-end audio electronics company founded in 1976 by designer Tim de Paravicini. Based in Cambridgeshire, England, the firm built its reputation on valve (tube) amplification, debuting with the EAR 509, a 100-watt monoblock power amplifier that has remained in the catalog for decades. Each unit is hand-assembled start to finish by a single engineer at the company's UK facility.

The brand's catalog centers on tube integrated amplifiers, power amplifiers, preamplifiers, phono stages, and headphone amplifiers, with long-running models including the 834P phono stage, the 859 and V12 integrated amplifiers, the 861 and 509 power amplifiers, the 912 tube preamplifier, the 868 preamp, and the HP4 valve headphone amplifier. De Paravicini, who previously served as chief amplifier designer at Luxman in Japan in the 1970s, was also known for original research into ultrasonic resonances in amplifier circuits and the subjective effects of distortion.

Beyond consumer hi-fi, EAR's tape electronics, microphones, and mastering gear have been used in professional studio contexts, with reported users including Pink Floyd, Kate Bush, Lenny Kravitz, and mastering engineers such as Bob Ludwig and James Guthrie. The company operates under the EAR Yoshino name, reflecting a long partnership with Japanese distributor Yoshino Trading.

Esoteric Audio Research has 2 products cataloged on Equipboard, including Effects Processors. Their gear is featured by 11 artists, with the strongest followings in Electronic, Rock, and Pop. Notable users include David Gilmour, Chris Stapleton, and Chris Martin.