> Every single key on a grand piano keyboard is weighted differently. This is because the strings for each note are slightly thinner and shorter in the treble register, becoming thicker and longer towards the bass register. As a result, there is greater resistance when playing low notes than when playing high notes. In other words, a heavier touch is required in the left hand and a lighter touch in the right hand. To emulate this in a digital piano, the keys are often individually weighted, with the lower keys heavier than the higher ones — something that’s called graded weighting.

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