WARNING: ONLY READ IF YOU'RE A BIT GEEKY ABOUT MELODEONS
Suggested DG 2.5 row melodeon layout
There's lots of good music to be played on an ordinary 2 row 8 bass diatonic accordion, enough that you might never get bored of the possibilities available. However, for my purposes, which include playing in bands where I might not have any choice about the repertoire or key, it's important to be able to play tunes in a wide range of keys, often with accidentals, and to be able to play good left hand accompaniment for all of them. Some players go the way of having multiple instruments to play in different keys, but this would cause a few problems for me. A band may want to do a set with a funny key change in the middle (D to E, G to Bflat, etc.) and I might not have time to switch instrument. Some tunes have different parts in different keys and I need to be able to play those. Some tunes have accidentals that may not be workable using the chin end of a 2 row box. For these reasons, and others that are simply practical and logistical, I've always preffered having one box that will do everything I need it to.
This is the layout I've been using for the past 5 years or so. It's fully chromatic* from low G (the lowest note in most folk tunes as it's the lowest note on a fiddle) up to the D two and a half octaves above (higher than most folk tunes will go). I find it works well for all the keys I ever have much reason to play in, which are the major keys of Bflat, F, C, G, D, A, E and minor keys of G, D, A, E, B. I know it can also do a decent job of Eflat and B major, and C and Fsharp minor, but it's rare that I ever need to play in these.
Important differences between this and the standard Castagnari and other common 2.5 DG layouts are:
- 4th buttons start, allowing room for low notes and low accidentals
- low octave G scale, often called "Anahata layout"
- Fs in both directions, allowing for F with the left hand B flat, and with push D for D minor tunes
- No push C or E. I never really find this to be a problem.
Note that the thirds in the chords can be switched off. If your box doesn't have a stop for this and you want to play in lots of keys, I recommend taping off the thirds.
Several of my pupils now have boxes with this layout and get on very well with it.
*2021 update: the lowest button on the D row used to be Bb/G#, which made the accidentals pleasingly logical and repetitive and meant the box was chromatic right down to low G. However, in practice I found I just never needed the low G# so I had it changed to a low pull B, which does come in handy.
Here is my 3 row 18 bass GC layout:
In order to achieve maximum versatility, it has become fairly usual for GC layouts to reverse the Gs and As on the C row, as in some Heim layouts. It's sometimes called a "Dutch reversal". In the widely used Milleret/Pignol layout the C row's push Gs are changed to As but the pull As are changed to G#s. I used this approach on my own layout because I was already used to using the pull G on the accidentals row, and this also keeps fingering more consistant with my DG layout. This makes the layout completely chromatic on the pull.
My layout differs from Heim and Milleret/Pignol in having a Bb on the push. Just as I find the push F essential for playing in flat keys on my DG, so I wouldn't want to be without the push Bb on my GC. The only commonly used GC layout with Bb both ways is Corgeron layout, which I'd recommend to anybody wanting a 3 row GC layout with a standard C row.
Finally, here is my "maybe some day" 3 row 18 bas DG layout, using the same accidentals row as my GC (moved up a fifth of course) and shifted up to fourth buttons start: