For Irish whistle, it is easier to play high D whistle than low D whistle. How about bamboo flute? Is it easier to play higher key bamboo flute (such as low G) than lower key bamboo flute (such as low D) or vise verse and why?
G or F are more manageable sized flutes.
Well there are people with much more experience of bamboo flutes than I have but maybe a newbie’s view will be of some use. I have Olwell bamboo D and F flutes.
I find the F much easier to play than the D. I have been told that this is unusual for a new player because my embouchure is naturally pretty slack and this ought to make it harder to hit high than low notes. I think the reason is this. The stretch on an Olwell bamboo D is quite hard to manage whereas the stretch on the F is comfortable. All my other flutes (wood, Boehm, PVC) are D flutes and the stetch is not nearly as hard to manage. They are all easier to play than the Olwell D. The stretch problem I think affects my playing not primarily in making me tire more quickly but in making it much harder to get a proper seal on the holes. Now, I’ve only tried Olwells so I don’t know if this problem with stretch is one you’ll encounter with other bamboo Ds.
Bamboo flutes, partly because they’re cylindrical, I think,
often have a long stretch, especially on the right
hand.
I have a TallgrassWinds bamboo in D and Eb, and an Olwell in Bb.
The D and Eb are fine for me, but this might speak more to the fact that I have large hands 
The Bb is small and there is no way I can play it, my fingers simply can’t bend at that angle and move at the same time, keeping the holes well covered. But it’s pretty.
My point is, all hands are different! However, the general consensus on this board seems to be that some flutes (like that in F ) seem generally to be a better fit ~ for most of those players who have tried them ~
Mary
Thanks all of you for responsing my questions. I have a low G bamboo flute. One of my problems is embouchure and breathing, when I play the 2nd octave and I couldn’t get it no matter how hard I try to blow the air. Besides I did something wrong, is low D bamboo flute more friendly for embouchure and breathing then low G bamboo flute?
It’s possibly easier to get a tone from the low D,
but another serious possibility is that something;s
the matter with your G flute. The high D flute
is tough going, at first; by the time one
gets down to middle G, it should play. Best