The transposer is a tool designed to facilitate the transposition of music from one key to another. Transposing can be useful when a song needs to be played higher or lower to better suit a vocalist’s range.

Components:

Central Scale: Positioned in the middle are the steps arranged according to functional theory:
I (Tonic)
II (Subdominant Parallel)
III (Dominant Parallel)
IV (Subdominant)
V (Dominant)
VI (Tonic Parallel)
VII (Diminished Seventh Chord)

Sliding Rulers: Positioned above and below are two sliding rulers containing all the notes of the major scale.

Chords: Located at the top and bottom, the chords resulting from the ruler positions are displayed.

Capo Guide: The number between IV and V indicates the fret where the capo should be placed, or if it’s already placed, how many frets it should be shifted.

Transposition Process:

Setting the Upper Ruler: Adjust the upper ruler to the key in which the music piece is currently written. For example, if the piece is in the key of ‘C’, align ‘C’ with step ‘I’.

Setting the Lower Ruler: Adjust the lower ruler to the key into which the music piece is to be transposed. For instance, if the piece is to be transposed into the key of ‘A’, align ‘A’ with step ‘I’.

Result: The chords of the original music piece can now be transposed by simply replacing them with the chords directly below on the lower ruler. Please note that the rule applies to any chord and is independent of the chord type. For example, if the upper ruler shows Dm and the lower one Gm, any D chord can be transposed to a G chord. A D7 therefore becomes a G7.