Handmade: an instrument that is either A: completely handcrafted top to bottom, or B: an instrument whose vital parts are handcrafted/finished/fitted.
The only person I know that completely handcrafted modern flutes closest to your description of A was probably Albert Cooper(post 20th century). Regarding B, which parts do you consider to be "Vital"
Ultimately in my book, in order to be considered handmade, it must have more parts that are handmade/hand fitted/assembled than parts that are machine made and assembled.
Let me play Devil's advocate here. There are machining operations that are much more precise than a craftsman can do by unaided. Why therefore is the handmade considered better when the machine produced parts can achieve higher tolerance levels for precision?
Instruments that feature handcut headjoints, hand cast/fitted/swedged keys, hand soldered toneholes/hand drawn toneholes, padded with premium pads by hand to the highest tolerances, and the list goes on.
I find the "handcut" headjoint phenomenon intriguing since I witness what happens in a lot of pro flute makers shops. Also, I would take a part cast with modern casting equipment anyday over one that was "hand cast".
Machine Made: instruments that are predominantly made by machines, and see very little (IF ANY) hand fitting/assembly/finishing. Instruments that have machine drilled/produced headjoints with no handcutting, keys that are stamped out by the thousands by a machine, then assembled by a machine, flutes that are padded by a machine and are then subjected to hot water and pressure to make sure the pads seal correctly, etc.
I think you would be surprised to see how much hand work goes into even the cheapest flute. Why is handcutting a headjoint important? Does it matter if the craftsman uses a hand scraper, hand operated bit, or a machine? Shouldn't the skill of the craftsman take priority over the choice of tool chosen to accomplish a task?
A Gemeinhardt or an Armstrong flute is most likely going to be a well made instrument in terms of durability and is a quality instrument in that regard, but a poor quality instrument in terms of advanced playing capabilities when compared to a Powell.
Why? (playing Devil's advocate again). I understand what you mean about the differences, but what are the determining factors precisely. I can't abide by the key construction argument, there are many ways to make a good strong key, so what makes the difference between these two?
Many of these things are completely relative and my personal opinion.
Understood, but this is for lively discussion purposes...