piano touch keyboard experiment

Thanks sigasa for your reply. I assume that your own purpose was to come up with a compensation calibration for keyboard uneven velocity response.

I bit more detail about the Sweetwater experiment, for people you don't have time to read the whole thing. Their purpose was only to measure the minimal force required to trigger and sustain a note. Only middle C was measured. A Yamaha grand was included for reference and the measured value was 96 grams. Keyboards tested (Roland, Korg, Casio, Yamaha, Digibel and Kurzweil) ranged from low seventies to above 100g.

I wished they included more than one acoustic grand (or even upright) in the test. Since they measured only middle C,I am curious about the range of values across the whole keyboard of an acoustic grand, as well as digital pianos /controllers that offer graded hammer response. Anybody?

The following could be useful if you want to run your own test:
I initially used AA batteries (!) that weight exactly 24 grams each. I established that the value for my FP80 was therefore between 72 and 96 grams. To further refine, I use a little plastic bottle (the kind that used to contain candy jimmies to decorate cakes!) because it is smaller in diameter than a piano key) filled with small steel beads used to clean wine carafes). I calibrated it using a kitchen scale accurate to about a couple of grams.