岡部啓一

Fourth World is a term coined by trumpeter-composer Jon Hassell to describe a "unified primitive/futuristic sound" that blends ambient minimalism, non-Western traditional musics, and studio electronics into an imagined global music. The style is characterized by modal drones, cyclical hand percussion, and timbral experimentation (often through harmonizers, delays, and pitch-shifting) applied to acoustic instruments—famously Hassell’s processed trumpet—alongside sampled or evoked elements of African, Indian, Southeast Asian, and other traditions. Rather than ethnographic authenticity, Fourth World proposes an imaginative, post-geographic sound world where the studio acts as a cultural crossroads. Musically it favors slow to mid tempos, layered polyrhythms, pentatonic or raga-like modality, microtonal color, spacious reverbs, and textural foregrounding. The result is meditative and sensuous, at once ancient-sounding and hyper-modern.

Video game music (VGM) is the soundtrack or background music composed specifically to accompany and enhance interactive gameplay. In its earliest decades, VGM was bound by severe hardware constraints: simple programmable sound generators (PSG) and later FM-synthesis chips limited composers to a handful of monophonic channels, basic waveforms, and tiny memory footprints. Those constraints forged a distinctive, catchy, loop-based idiom—often called “chip music” or “8‑bit”—that became the emblematic sound of early games. As technology advanced, VGM expanded into rich orchestral, rock, electronic, and hybrid palettes and adopted adaptive/interactive scoring techniques so the music could change with the player’s actions. Today it spans everything from intimate, textural ambience to full symphonic epics, while still celebrating its retro chip heritage.

Anime (often called "anisong" for vocal themes) is the umbrella term for songs and scores created for Japanese animation, including opening/ending themes and background music. It blends contemporary J‑pop/J‑rock songwriting with dramatic orchestral scoring and modern electronic production, aiming for instantly memorable hooks and emotionally charged climaxes tailored to a show's narrative and characters. Stylistic hallmarks include high-register, expressive vocals; tight, hook-forward structures (especially 90-second “TV size” versions); bright, polished production; and frequent late-song key changes. Arrangements often hybridize rock bands, strings, brass, and EDM textures to deliver cinematic impact, while lyrics favor aspirational, metaphor-rich imagery that mirrors the series’ themes.

Experimental electronic is an umbrella term for electronic music that foregrounds exploration and innovation over convention. It treats the studio, computer, and synthesizer as laboratories, using techniques such as tape manipulation, modular and software synthesis, feedback systems, granular and spectral processing, algorithmic/generative composition, circuit-bending, and field recording. Rather than regular song forms or dancefloor functionality, it prioritizes timbre, texture, space, and process. Structures may be nonlinear or open-form; harmony is often non-functional or drone-based; rhythm can be free, irregular, or machine-deconstructed. The style overlaps with electroacoustic music, sound art, industrial, ambient, and noise while continually interfacing with club culture and contemporary art contexts.

Soundtrack is music created to accompany and enhance visual media such as film, television, and video games. It includes original scores (instrumental or vocal music composed specifically for the picture) and, at times, curated compilations of pre-existing songs. Stylistically, soundtrack is a meta-genre that can encompass orchestral symphonic writing, jazz, electronic and synth-driven textures, choral forces, popular song, and experimental sound design. Its defining trait is functional storytelling: themes, motifs, harmony, rhythm, and timbre are shaped by narrative needs, character psychology, pacing, and editing. Common features include leitmotifs for characters or ideas, modular cues that can be edited to picture, dynamic orchestration for dramatic range, and production approaches that sit well under dialogue and sound effects. Because it must synchronize to picture, soundtrack often uses clear dramatic arcs, tempo maps, and hit points.