The above two photographs show the front and rear view of keywork on a closed hole offset G-key flute, fitted with a split E mechanism.
The main feature of the mechanism is the small curved lever which can be seen actuating the right hand offset G key on the lower photograph. The rod between these two offset G keys is split so that the two keys can move independantly.
When the key used by the second finger of the right hand is depressed the split E actuating lever also depresses the one offset G key leaving the other one in the open position.
When the keys operate as described above the production of top E (E3) is facilitated.
There are disadvantages in that some trills (G3/A3) are virtually disabled.
The above mechanism is simply fitted to an offset G flute as can be seen above, but a totally different mechanism has to be used to actuate a split E on in-line G key flutes. This mechanism has been found to be unreliable on some flutes and hence a split E is rarely found on in line mechanism flutes.
Opinions on the merits of split E mechanism are diverse
The flute illustrated above is a Silver Muramatsu Flute of about 1980 vintage. The split E mechanism was fitted after purchase of the flute
For more information on this subject go to The
FAQ on the Larry Krantz Web Site
The above photograph and notes are as accurate as my knowledge on the subject permits.