One of the most basic formulas.... (cont.)

- math -

Howdy all!

Okay, let's continue from where we left off yesterday....

Making the sound mechanism for our flute, we need to know a couple of things. Number one, the placement of the embouchure (the hole you blow into, or across) - that is to say, the *centerpoint* of the hole to be drilled for it - should be one flute diameter's width distance from the wall face of the plug in the flute's interior.

So, in this case, our PVC flute's inside diameter being 3/4", we measure 3/4" from the face of the closed end (it's *interior* face), and mark this point on the outer wall of the flute's body.

Number two, the embouchure's hole size should be HALF that of the flute's inside diameter.

Once we drill that hole in, we then need to bevel one of it's edges - which edge to bevel would be depending on whether you're left-handed or right-handed. We want the outer surface of the flute untouched - we will be beveling the airstream splitting edge from the inside. Take a small file (needle files often work best for me), either a full round or a half round, and file this to a sharp edge.

Okay, now try blowing across it. No sound? Well, this takes a bit of practice.... first of all, you don't want the shape you make with your lips to be as though you're whistling - forming a round hole - you instead want to form a slot-like opening. Some flute teachers say, "pucker and smile". You may also try configuring your top and bottom lips in a certain way - while blowing, try moving your bottom lip more forward than your top one, then move your lips to the opposite of this. This focuses your blowing to direct the airstream to flow up and down, until you find the best direction to split the airstream across the blowing edge and make a sound. Keep practicing this way until you hear sound being created.

Got any sound coming out of it yet? Great!

Now we need to properly tune this flute. To figure out other notes' frequencies, using the mathematical formula in the previous post to find the flute length needed for future flutes, or to find (again, using the math) where the fingerholes of this, and other flutes need to be, click here for a good site with this information.

Next, we'll need to have something to use to tune our flute with - a nifty bit of freeware to use as a tuning tool - this is called "minituner", and though it is promoted as a tuner for guitars, it can actually tune any instrument using your computer and a microphone - simply click on "view", then choose "chromatic tuning", and you're all set! To go to the page for the free download, please click here.

Okay, to bring this experimental A flute's body length to the proper note's half-wavelength size, we will remove bits of the PVC's open end a little at a time, until we achieve the right sound. Remembering to measure from the wall face of the plug from the *inside* of the flute, go ahead and chop it down to 16" or so. Remember to remove any burrs and particles from the edge of the cut so as to not allow any of it to interfere with the airflow and affect the sound.

Try it out with the minituner program (or tuning pipes, or electronic tuner, if you have any handy), and see what note it registers at - is it lower than A? It needs to be shorter then. Take off just a little more, and try it again. Keep at it until you have reached A.

You may notice that, depending on the angle from which you are blowing into the flute, that you can sharp of flat the note - make it sound higher or lower. Keep this in mind while you are tuning your flute.

Okay, that's it for today's post - next, we'll find the fingerhole placements, and put them in, finishing our first flute together - more in the next post!

Have a nice night! ^_^

- math -