The Casio PX-870 remains a benchmark for the furniture-style digital piano market under $1,000. While Casio was once viewed strictly as a budget alternative, the PX-870's AiR Sound Source and 40-watt, four-speaker Sound Projection system deliver a depth of field that rivals more expensive Yamaha Arius models. The concert grand patch is particularly lush, benefiting from adjustable string and damper resonance that adds a convincing layer of organic 'air' to your performance.

The Tri-Sensor Scaled Hammer Action II provides a satisfying, tactile weight. The simulated ebony and ivory textures are a highlight, offering superior grip during long practice sessions, though the action can feel slightly 'bouncy' on the key return compared to a high-end acoustic. My main gripe lies in the user interface; like many minimalist consoles, changing deep settings often requires memorizing cumbersome key-button combinations, which feels a bit dated. However, the inclusion of the 'Hall Simulator' and a dedicated USB-to-device port for MIDI/audio recording makes it a versatile tool for the intermediate student. It's a workhorse that prioritizes acoustic realism and projection over flashy digital bells and whistles, making it an excellent value for home learners and budget-conscious enthusiasts who need a primary practice instrument.

The Casio PX-870 represents Casio's most piano-focused home digital piano in the Privia line, and its combination of sound quality, key action, and furniture-style cabinet makes it a strong contender for dedicated home practice. The AiR sound engine with multi-dimensional morphing produces piano tones with impressive dynamic range -- the transition from soft to loud playing reveals tonal shifts and harmonic changes that approximate the behavior of an acoustic instrument. The tri-sensor scaled hammer action provides a realistic playing experience with three contact points per key for improved accuracy during rapid passages and repeated notes. The simulated ebony and ivory key surfaces add friction and moisture absorption that enhance control during expressive playing. The four-speaker output system, with two speakers positioned downward to reflect sound off the floor, creates a surprisingly immersive listening experience that fills a room effectively without external amplification. The slim cabinet design fits comfortably against a wall without dominating a room. The lid simulator and string resonance features add subtle realism. The PX-870 focuses on being an excellent practice instrument rather than a feature-laden workstation, which means limited non-piano sounds and no Bluetooth connectivity. For pianists who want a dedicated, realistic practice instrument in an elegant home-friendly package, the PX-870 delivers genuine musical satisfaction at a competitive price.