A Boehm flute is a D flute, isn’t it?
I thought a Boehm flute’s ‘natural key’ was C but was corrected in my mis-understanding by Geert Lejeune. A Boehm flute is intrinsically a D flute (albeit with a C foot). It’s not a C flute despite the easy (keyless) F-nat and the complicated (ugly, keyed) XXXOOX for F#. Having the reach down to C4 (middle C!!) is just the cherry on top not the root toot of the flute 🙂
The flute is named for its XXXXXX note the all fingers down D. And for it’s octave the OXXXXX note - D’. And, were the Boehm a C flute you wouldn’t have the ‘all fingers off’ C#, it’d be a B. Further… when a Boehm flute has a B foot we wouldn’t now call that a B flute.
If I now understand the labelling - when the flue is referred to as being in the family of C-instruments - this refers to the fact that play C, sounds C; it is not a transposing instrument.
Or have I got this entirely wrong (it has happened before, frequently)?
An interesting aside - in classical Indian flute traditions (Carnatic venu and Hindustani bansuri) the instrument is named according to the XXXOOO note. So our D flute would be called a G.