Compact yet versatile, the Casio SA-81 is a 44-mini-key portable keyboard designed for beginners and enthusiasts alike. Though small in size, it packs 100 high-quality built-in tones, including realistic piano voices, as well as wind, percussion, and more, all sampled from acoustic instruments. With 32-note polyphony, it ensures that overlapping notes still sound clean and full. Performance features include layer mode, sustain, reverb (ROOM, HALL 1, HALL 2, STADIUM), octave shift, transpose, and adjustable tuning down to 0.1 Hz increments. For musical accompaniment and practice, it offers 50 rhythm patterns and 10 built-in songs (play along or mute the melody to practice). The interface is intuitive, with tone-direct buttons for quick access (e.g. piano, trumpet, drums) and a three-level full-dot LCD display for clear feedback. The SA-81’s chassis measures approximately 604 × 211 × 57 mm and is powered either by 6 AA batteries or an AC adapter (sold separately). In its sleek black-and-white aesthetic, it strikes a balance between playful portability and musical functionality.