Hello all I personally regulate the let off by touch. I depress the key until I feel the resistance of the let off button. Then I stop. Then I give the key the last motion to make the let off occur. I regulate the let off so that in that case I still can hear a sound of the hammer touching the string. This, of course, is too close for every situation. I then depress the forte pedal, and try to give the key what pianists call a half way playing (you play the key, but you don't use the full key dip, you only go to about half the key dip, and the note plays very quietly). I then re-regulate the let off so there is just enough aftertouch to avoid any double striking. Typically, I have to go back one quarter of a turn of the let off button. Of course, this regulation does need to be redone every week. For more lasting regulation, I just give blindly one more half a turn to the let off button. Stéphane Collin (Brussels, belgium)
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