Stuart & Sons 102-key Concert Grand Piano l� c�y ?�n piano ??c ?�o nh?t th? gi?i v?i ph?m vi 9 qu�ng t�m ??y ??, t? Do d??i c�ng ??n Do tr�n c�ng (C0-C8). ???c ch? t�c b?i Wayne Stuart t?i �c, ?�y l� c�y ?�n piano l?n nh?t v?i 102 ph�m, m? r?ng gi?i h?n c?a thi?t k? piano truy?n th?ng. �m thanh ??c bi?t trong tr?o, gi�u h�a �m v� c� ?? b?n �m (sustain) l�u nh?t th? gi?i, l�n ??n 3 ph�t.