Looking back at Mr. Ferrarelli's lesson on the recording of a grand piano, I am asking if the key dip of the white keys is, let's say, 10, what would that of the black keys be?
then, how do you record the stand spring under the repetition lever (the one shaped like an inverted V).
Generally, the black key is a little less deep. It depends on the aftertouch. The white key should have the same aftertouch as the black one. If not, you can slightly increase the level of the black key relative to the white one.
The spring in question is adjusted with the appropriate hook tool. By lifting the upper part out of its seat, it can be tensioned. Instead, to release tension, the lower part is "massaged".