The Native American flute has two chambers. Air enters the first chamber and is forced upward by the wall between the two chambers and out through on an opening in the top of the flute. The air is then redirected into a hole in the second chamber by a block (also known as a bird or fetich) affixed to the top. As the air enters the second chamber, the sound is created. Because the block plays such an important role, make sure it's positioned properly
Make certain the bottom leading edge of the block is lined up with the back of the hole and centered & firmly affixed. Later you may wish to experiment by varying the position back and forward 1/32 to 1/16 of an inch.
1. The tuning of the flute,
2. The nature of the wood from which the flute is crafted,
3. The finger placements over the holes,
4. The force of the air by the player,
5. Position and firmness of the block.
Check the Block - The positioning of the block determines the pitch of the flute when played. The bottom leading edge of the block can be lined up with the back of the hole to produce a pitch of approximately 432 HZ on most flutes. Sliding the block up to slightly above the back of the hole will produce a pitch of approximately 440 HZ which is most compatible with other instruments. Wherever the block is positioned it must be tightly tied and centered to prevent air leaks.
Posture - Head erect, elbows and flute several inches away from your chest. This posture facilitates proper breathing.
Holding your Flute & Finger Placement - The middle three finders of each hand cover the holes of a six hole flute and the forefinger and middle finger of your top hand and the middle three finders of your bottom hand cover the holes of your 5 hole flute. The "textbook" method is left hand on top but many fine players place the right hand on top. Experiment both mays to find which is most comfortable for you.
Pads vs Tips of Fingers - The holes are covered by the pads of the finger, not the tips. Covering the holes with the pads of your fingers best assures the total coverage which is vital.
Producing Sound & the "Sigh" - Sigh into the flute rather than blow. With all holes covered, you should get a low mellow sound. Technically, the top lip is pulled back against the upper teeth and the flutes rests on your lower lip, but this is far less important than breathing gently (sighing) into the flute rather than "blowing". Of you hear a squeal, you are failing to completely cover all holes. If you get a sigh sound, you are over blowing. There are a few fingers combinations that work best with "overblow" particularly on notes with the top holes open and lower notes closed. You will discover this as you practice the drills.