What is the main difference between the Yamaha P-225 and Casio PX-S1100?

They're built around different priorities. The P-225 focuses on sound quality — its CFX Concert Grand engine with VRM Lite is warmer and more dynamic than the Casio's AiR engine — and has a more powerful 4-speaker system. The PX-S1100 prioritizes portability: it's the world's slimmest 88-key piano (9.1 inches deep), runs on AA batteries, and has Bluetooth MIDI for wireless app connectivity. The P-225 costs $80 less.

Does the Casio PX-S1100 have Bluetooth MIDI?

Yes — the PX-S1100 includes a WU-BT10 Bluetooth adapter in the box that enables both Bluetooth MIDI and Bluetooth Audio. This allows apps like Simply Piano, Flowkey, and GarageBand to connect wirelessly for note detection. The Yamaha P-225 has Bluetooth Audio only — it can stream audio wirelessly but cannot send MIDI data over Bluetooth, so app connectivity requires a USB cable.

Can the Casio PX-S1100 run on batteries?

Yes — the PX-S1100 runs on six AA batteries for approximately four hours of play. This makes it the only piano in this class with genuine battery-powered portability. The Yamaha P-225 requires AC power. For players who practice in different locations, travel, or might busk, battery power is a meaningful practical advantage.

Which sounds better, the Yamaha P-225 or Casio PX-S1100?

The Yamaha P-225 sounds better in most listening contexts. Its CFX Concert Grand engine — Yamaha's flagship sample — is warmer, more dynamically expressive, and benefits from VRM Lite resonance modeling. Through headphones the difference is noticeable: the P-225 has more depth and a more convincing piano decay. The Casio's AiR engine is clear and modern-sounding, but has less musical richness at quiet dynamics. The P-225 also has more speaker power, so it fills a room better at higher volumes.

Is the Casio PX-S1100 really the world's slimmest 88-key piano?

Yes — at 9.1 inches (23.2 cm) deep, the PX-S1100 holds this distinction. For comparison, the Yamaha P-225 is 10.7 inches deep. That difference matters when placing the piano on a standard desk (typically 10–12 inches deep) or in a small room where wall clearance is limited. If slim profile is a priority, no 88-key piano at any price gets thinner.

Does the Yamaha P-225 have better speakers than the Casio PX-S1100?

Yes — the P-225 uses four speakers with higher total wattage versus the PX-S1100's two 8W speakers (16W total). The Yamaha sounds fuller and louder in a room, with better stereo imaging. The Casio's speakers are adequate for individual practice but don't project as well at higher volumes. For a living room or practice room where you're playing without headphones, the P-225's speaker advantage is noticeable.

Which is better for a beginner, the Yamaha P-225 or Casio PX-S1100?

Both are excellent beginner instruments. The P-225 is the simpler recommendation: it sounds better, costs less, and has physical controls that are more intuitive than the Casio's touch panel. The PX-S1100 makes sense for beginners who specifically need Bluetooth MIDI for app-based learning (Simply Piano, Flowkey) without wires, or who need battery power. If neither of those applies, the P-225 is the more straightforward pick.