Founded in 1983 in Nordenham, Germany by Karl-Heinz Sonder, ABACUS electronics evolved from industrial measurement and control technology into a renowned HiFi manufacturer. Originally developing electrotechnical products, Sonder pursued his passion for audio reproduction, establishing proprietary 'Dolifet' amplifier technology exclusive to ABACUS. The family business celebrated 40 years in 2024, with leadership transitioning to son Hanno Sonder, a physics engineer raised with ABACUS technology. Operating from 1,000 square meters across four floors, the company employs nine core staff plus university students and interns from Oldenburg studying audio technology and engineering physics. Known for the C-Box series including Germany's '#1 studio monitor' C-Box 3, ABACUS handcrafts all products in Germany, focusing on technical excellence over marketing. Shipping 150-200 packages monthly with 90% sales in German-speaking regions, ABACUS represents authentic German audio engineering tradition.