Why transpose at all?

A tune that sits beautifully under your fingers in G can feel like a wrestling match in D. A singer arrives at a session wanting a song a tone higher than the one you learnt. A fiddle player launches into a set in A and you'd like to join in without three bars of silence. Transposing on the Anglo isn't gymnastics; it's about knowing where your comfortable keys live and moving a melody between them without fuss.

Know where your keys live on the rows

Everything on an Anglo comes back to the rows. On a standard C/G instrument the two main rows sit a fifth apart, and each carries a complete major scale. The C row gives you C major, with F natural on the pull. The G row gives you G major, with F sharp instead. That single difference — F natural against F sharp — decides whether a tune will slide across from one row to the other unchanged.

From those two home keys you get a generous set of related modes for free:

• C major and G major — the two home keys.
• A minor and E minor — the relative minors, both very comfortable.
• D dorian and A dorian — common in English and Irish session tunes.
• G mixolydian — no F sharp needed, so plenty of tunes with a flattened seventh work well here.

On a 30-button, the extra accidental row opens up keys such as D major and A major. On a 20-button you simply don't have the C sharp, so D major isn't available in full — worth remembering before you promise to play a tune in D.

Think in numbers, not note names

The quickest way to transpose on any Anglo is to stop thinking in letters. Learn the tune as a set of scale degrees — 1, 2, 3, 5, 6 — and moving it becomes a mechanical exercise rather than a memory test. A melody you know in G isn't a different tune in C; it's the same shape with a different starting point.

In practice:

• Find the tonic — the note the tune resolves to.
• Hum the melody as numbers rather than note names.
• Play the scale of the target key first, so your hands know the shape of the new home.
• Rebuild the melody degree by degree, checking each phrase before moving on.

The row-shift trick

Because the C and G rows mirror one another a fifth apart, an enormous number of tunes can be moved simply by playing the same fingering a row over. A melody learnt on the C row can often be played on the G row, a fifth up, with the same push and pull pattern. The catch is the seventh degree: what was F natural on the C row becomes F sharp on the G row, so any phrase touching the seventh needs adjusting. Watch the range too — the shift will push high notes past your top button or pull low ones below your lowest.

For anything more ambitious, cross-row fingering is your friend. Playing across both rows gives smoother bellows control, more options in the upper register, and access to keys neither row supplies alone. It takes longer to bed in, but it's the biggest single upgrade to your transposing flexibility.

Choosing chords that suit the new key

Transposing a melody is only half the job — the accompaniment has to move too. On the Anglo, the easiest chords are those lying entirely on the push or entirely on the pull, because you can sound all the notes with one bellows direction. C major is a push chord. G major and its relatives sit comfortably on the pull. Am and Em are forgiving either way.

Keep it simple and let the chords do the work:

• Two-chord tunes — most folk melodies survive happily on the tonic, the chord a fifth above, and their relative minors.
• Drop the fifth — in a chord like C major the third (E) carries the flavour. If the fifth is awkward to reach, leave it out.
• Bass on the left, chord on the right — a single bass note under the melody is often more musical than a full chord on every beat.
• Mind the bellows — a key that forces you onto the pull for long stretches changes where you run out of air, so plan your breaths again.

When the key you want isn't there

Some keys won't fit on some instruments, and no amount of clever fingering will conjure a C sharp from a 20-button C/G. You have four honest options: play the tune in a related mode that avoids the missing note, move it down to G or C, borrow an instrument in a friendlier key such as G/D, or invest in a 30-button.

One last practical point. If transposing takes you onto an accidental you rarely touch — a G sharp, say, or a low F sharp — give it a proper listen. Reeds that sit idle for months can drift flat, respond slowly, or suffer from a tired valve, and it isn't the transposition that's at fault. Test those notes in your warm-up, keep the bellows pressure even, and have anything weak looked at before you blame your new key. Knowing the layout is half the battle; keeping the instrument healthy is the other half.