F-90: How to transpose the F-90 January 30, 2023 06:13 Updated Follow Use the following procedure to transpose the F-90. 1. While Holding down [Variation] and [Demo], Press the tonic root. ( C2 - B2 ) Related articles DP-90se: How to play songs from a USB flash drive F-20: Changing the Key of the Keyboard (Transpose) JX-03: Transpose FR-1X: How to use the metronome C-30: Transposing the Keyboard