Blind lutenist singer mentioned by Tinctoris in his commentary on the lute.
lockwoodF p. 105 quotes a letter 22 August 1468 from Maria Sforza to her mother “Yesterday we did not go out into the countryside but, while we were dining, we had various amusements in the playing of harpsichords and lutes, and by the jesters, and by Master Giovanni Orbo. who recited in a marvellous manner, quite out of the ordinary.” {Lockwood gives original too.
gasserM, p. 172: Giovanni [Joanne] Orbo flourished between 1465 and 1510 in Munich, Mantua, Ferrara and Milan/ He was a blind musician credited with intrducing playing with the fingers instead of the plectrum according to a statement by Tinctoris (De inventione et usu)