Eon Research is a boutique audio equipment maker based in Thessaloniki, Greece, founded by P. Athanasiou, an electronics engineer with over 25 years of experience in the audio industry. The company designs and handbuilds guitar effects, processors, and amplifiers that blend vintage audio technology — including new-old-stock Soviet miniature vacuum tubes and hand-picked vintage components — with modern manufacturing techniques such as CAD design, laser cutting, and CNC machining. Each piece is finished by hand and fine-tuned by ear.

Eon Research's flagship product is the Fos, a tube-driven high-gain overdrive/distortion pedal housed in a distinctive enclosure of mirror-polished steel and beeswax-stained exotic wood. The Fos uses NOS Soviet pencil tubes in a fully analog circuit, producing everything from transparent overdrive to extreme high-gain distortion. True to the company's artisanal ethos, the Fos is produced in limited numbered runs of 50 units, with each pedal undergoing a burn-in period and rigorous quality testing before shipping. Eon Research also offers custom one-off equipment designed to a client's specific needs, serving a clientele of studios, radio stations, and professional and amateur musicians across genres.