I can have the loudest sound (and I played with professional and famous djembefolas), and my hands are soft.
It depends on your morphology, and on your technique.
My explanation for this is that with practice you learn to have more sound with less contact from your hand on the skin.
This is not true however if you play on cow skin. If I were to play on those skins regularly, I am sure my hands would be more callous.
Also I don't know what would happen if I were to play 8h a day for months, like many ballet players. Maybe I would get a hard hand. That's why djembefolas with a killer technique can still have a hard hand, it's because of the amount of time spent on the instrument.
Toughening up the hand is surely part of the process, but they are different way of toughening it.
The most important one to me is when key areas of your hand get toughened so that you don't bleed anymore from them (eg: fingertips).
But it's another level when you get your hands hard as wood. It happens to very strong and skilled players.
Would the hand become less hard with more technique ? I can't say. Would it soften if they practiced less hardcore ? I think so.
But does callousness = technique ? I don't think so. The people I know who have outstanding technique don't have hard as wood hand.
Maybe people who have harder hands are less sensitive so they hit the skin stronger ? I can't say, maybe.
Hope it helps.
Kawa
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