In my review in Tempo 175 of the Etcetera disc (KTC 1071) of Lou Harrison's pieces for guitar and percussion, the Well-tempered Guitar was described as ‘a clever adaptation to magnetically adjust the frets on the guitar to produce alternative tunings’. This is misleading, and should have read ‘a clever adaptation using interchangeable fingerboards to produce alternative tunings’. It is the fingerboards that are held magnetically, not the trets themselves, so there is no possibility of individual frets or portion of them moving about the fingerboard (a guitarist's nightmare!) Mea culpa.