This is the so-called critical weight. We usually call it "the weight of the hand". A keyboard is about 50 grams, the world standard keyboard weighs 40-42, and the Yamaha keyboard weighs 45-47, so the Yamaha keyboard is light, and the general brand keyboard is partial, so the world standard is light.

But being light or heavy doesn't mean playing well or not. Besides the weight of the keyboard, it is also related to its beat and the length of the strings. The combination of the "reflection speed" of the keyboard and the key weight produces the "feel" when we play. To produce a good "feel", the "reflection speed" must be fast (for example, you can play more than seven times a second, and grand piano is more than an upright piano.

What about the heavy one? Is it better to be gentle? There is no "absolute" in this. For example, the German piano will be a little biased, so the timbre will be more vigorous and powerful, and most Europeans are stronger and taller. For us Asians, the German piano is partial, but in their hands, it may be just right. So whether it is heavy or light depends on personal habits. There is also the strength needed to play tracks, and a light keyboard will reduce the loss of physical strength.