Sound Horizon (サウンドホライズン)—abbreviated as Sanhora by fans—is a Japanese musical project led by composer Revo. The group bills itself as a "fantasy band" and has built a devoted following around their concept-heavy approach to music.

What makes Sound Horizon distinctive is how they structure their albums. Rather than standalone songs, each record is designed as an interconnected story told across multiple tracks with different narrative threads that weave together into one larger narrative. This omnibus style is core to their identity.

Vocally, they favor soprano and mezzo-soprano singers, and narration—often performed by professional voice actors—plays a major role throughout their work. There's a heavy anime influence baked into their sound, which became even more pronounced once they landed a major record deal and could afford to hire seiyuu for spoken passages.

Lyrically, Sound Horizon leans hard into mystery and metaphor. Their lyrics are densely poetic, often more cryptic than typical J-rock, and the themes jump between high-fantasy concepts (ancient curses, legends, wars, paradise) and deeply human emotional territory (forbidden desire, obsession, heartbreak, guilt). This tonal range—mixing the mythic with the intimate—is a big part of what keeps people coming back.

The band has cultivated a tight, engaged fanbase that treats their albums like interactive stories to decode and discuss.