April Music Stello HP100 Headphone Amplifier; HP-100

Stello is a hi-fi brand from South Korea, launched by April Music, a company founded in 1998 in Seoul. April Music, known for its skilled engineering team that includes musicians, established Stello as one of its three core lines—alongside the digital-focused Aura and power amplification-oriented Eximus—initially targeting personal audio enthusiasts. The brand debuted with the acclaimed HP100 (also known as H100) headphone amplifier and preamp, building a foundation in compact, high-quality components assembled in Korea with some enclosures sourced from California.

Stello specializes in digital audio essentials and amplification, including standout products like the CDT100 and DA100 DACs, USB DACs such as the U3, CD transports like the CDT200, and integrated amplifiers like the Ai500. Its 100 Series emphasizes lifestyle-sized designs that bridge traditional hi-fi with PC-based music playback, delivering transparent, open sound through reliable engineering. The lineup avoids speakers or turntables, focusing instead on sources, DACs, and amps that integrate seamlessly into modern setups.

Positioned as an affordable high-end contender, Stello earns praise for punching above its price with extraordinary build quality and musicality, often rivaling pricier rivals. It challenges preconceptions about Korean audio—proving South Korea's prowess beyond consumer electronics—while serving as a gateway for discerning buyers seeking value-driven performance without boutique excess. April Music's OEM work for other high-end marques underscores its technical credibility in the global market.