Original sentence: (2006) Liszt and his world.The famous virtuoso Franz Liszt, who played Graf pianos, must have been something of thorn in Herr Graf's side, as the Graf piano was not always capable of standing up to the violence that Liszt inflicted on it during his more impassioned moments of playing
Edited sentence: " Wieck described another concert on the same visit in which Liszt "destroyed" two Grafs, as well as an Erard piano lent to him by Sigismond Thalberg.(2006) "Just two words., Liszt and his world.Enormous success:  Liszt's 1838 Vienna concerts," in Christopher H.Gibbs and Dana Gooley, eds.The famous virtuoso Franz Liszt, who played Graf pianos, must have been something of a thorn in Herr Graf's side, as the Graf piano was not always capable of standing up to the violence that Liszt inflicted on it during his more impassioned moments of playing