Bruce,
Nice idea. Personally I hate the bis key and never use it, but it is an interesting idea for those who do. The small G# and/or donut has always felt like a tonal compromise to me. I much prefer split E. While you are at it, you might want to take a cue from the Murray flute, which splits the A touch between two keys and eliminates the clutch to allow for a split F#. With that you have perfect venting in the lower 3rd octave...
Toby
Nice idea. Personally I hate the bis key and never use it, but it is an interesting idea for those who do. The small G# and/or donut has always felt like a tonal compromise to me. I much prefer split E. While you are at it, you might want to take a cue from the Murray flute, which splits the A touch between two keys and eliminates the clutch to allow for a split F#. With that you have perfect venting in the lower 3rd octave...
Toby