Gregg Rolie

AOR (often read as Album-Oriented Rock and, in stylistic terms, Adult-Oriented Rock) is a polished, melody-forward strain of rock geared for FM radio and arena stages. It pairs sleek production with anthemic choruses, soaring vocals, and a balance of guitar crunch and prominent keyboards, aiming for broad appeal without sacrificing musicianship. In practice, AOR sits between hard rock and soft rock: tight rhythm sections, glossy multi-tracked harmonies, clean-to-overdriven guitar leads, and radio-friendly structures. Its repertoire spans driving uptempo anthems and emotive power ballads, with frequent key changes for climactic final choruses, meticulously layered arrangements, and lyrical themes of romance, resilience, and escape.

Arena rock is a radio-friendly, anthemic strain of rock designed to fill large venues with big choruses, powerful hooks, and polished production. Songs typically emphasize sing-along refrains, soaring lead vocals, and guitar riffs that are memorable after a single listen. The style blends hard rock punch with pop-rock concision, often adding keyboards, glossy harmonies, and dramatic dynamic builds tailored for stadium-scale acoustics. Power ballads sit alongside mid- to uptempo rockers, all arranged to encourage mass audience participation—clapping, call-and-response, and wordless "whoa-oh" chants.

Rock keyboard is a keyboard-centered approach to rock in which pianos, electric pianos, organs, Mellotrons, and synthesizers provide the primary riffs, harmonic foundation, countermelodies, and solos. Instead of guitars dominating the ensemble, the Hammond B‑3 with a Leslie cabinet, Rhodes and Wurlitzer electric pianos, Clavinet funk stabs, Mellotron strings/choirs, and analog/virtual‑analog synths (Moog, ARP, Prophet, etc.) lead the texture. Players draw equally from blues, classical, and jazz vocabulary, often featuring ostinatos, extended chords, modal color, and virtuosic soloing. The aesthetic ranges from gritty overdriven organ rock to symphonic, cinematic layers and synth‑driven arena hooks.