Buying guide
Weighted Keys Explained
Weight and touch sensitivity are different
Weighted describes physical resistance. Touch sensitivity describes how the sound responds to the way you strike a key. A keyboard can have touch-sensitive sound with very little physical weight. Changing a digital piano's touch curve can make a loud sound easier to trigger, but it does not change the mass or friction under your fingers. When shopping for a piano-learning instrument, verify both the mechanism and the sound response. The phrase full-size keys describes dimensions, not an acoustic-style action.
What hammer action and graded weighting mean
A digital hammer action uses a mechanical assembly to create resistance and movement associated with a piano key. It does not need strings to do this. Graded weighting means the resistance changes across the keyboard, generally heavier in the bass and lighter toward the treble. Manufacturers implement that progression differently. Neither the word graded nor the heaviest possible action proves quality. The useful question is whether you can control quiet notes, loud chords and repeated notes comfortably.
Wood versus plastic
Wooden construction can be part of an excellent mechanism, but the material is only one ingredient. Key length, leverage, return behaviour, cushioning and sensing all affect the result. Be precise about the claim: the Yamaha P-525 has wooden white keys, the Kawai CA501 has 88 wooden keys, and the Roland FP-90X uses a wood-and-plastic hybrid. These are not interchangeable descriptions. A wood-effect or ivory-feel surface also says nothing by itself about the material underneath. Try the whole action rather than ranking it by its surface label.
Pivot length and playing near the back
A key acts as a lever. Where its pivot sits influences how the resistance changes as your fingers move toward the back of the visible key. This becomes relevant in chords that place some fingers between the black keys. A shorter cabinet does not by itself tell you the pivot measurement, and we do not infer precise dimensions from marketing photographs. Try a comfortable chord first near the front and then deeper into the keyboard. Notice whether you can maintain even volume without strain.
Escapement simulation and sensors
On an acoustic grand, escapement allows the hammer to leave the mechanism and strike the string. A digital simulation usually adds a tactile sensation during a slow key press; it is not an acoustic hammer striking a string. Sensor arrangements help the instrument follow key movement, and additional sensing can support repetition without a complete return. Sensor count alone cannot establish how responsive an entire instrument feels. The mechanism, firmware and the player's technique still interact. Compare repeated notes at both soft and loud dynamics.
A useful ten-minute audition
Start with a quiet scale and listen for notes that jump out unintentionally. Play a chord softly, repeat a single note, and use a familiar passage with black keys. Try the default touch curve before changing it. Turn the volume down briefly to hear mechanical key noise separately from the speakers, especially if you share walls or practise at night. Then use the same passage on another instrument. A comfortable, controllable action for your playing is more useful than winning a checklist of wood, sensors and escapement.