# Homemade well tuned pan flute

9 Steps
I'm kinda strange guy. I like really zillions of things, very different one another. For example, I'm studing math, I'm learning to play violin, I like Irish music... I also like making things. To conciliate this last passion with music I made a pan flute, an ancient instrument belonging to various cultures. Here is the process that will bring us to an almost perfectly tuned pan pipes.

This Instructable is splitted in two parts: theory and practice. If you are not interested in all the math and physics behind the project, you can jump directly to the practice section. If you want to know how to retrive all measurement, or even to customize your pipes, then proceed with next step.

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## Step 1: Theory

The (not-so-)boring part.

As I've aforementioned, you can skip this passage if you don't want (or need) to understand the physics beyond a pan flute.

OK, if you're reading those words you want to know more. I'm here for this!

A pan flute is a mere group of tubes with a closed end (called closed cylinder, even if one end is open). Each tube have a different length but, usually, the same diameter of all other tubes.
The length of the tube influence the pitch: longer tubes produce lower notes, shorter tubes produce higher notes.
The inner diameter of the tube influence the speed of blow needed to make the sound audible: smaller diameter means less blow, greater diameter means more blow.

Pretty simple, uh? No math, no strange formulas...

Now we need to find a precise relation between tube length and note pitch. Luckily, some physician (well, actually a lot of physician) already studied this matter creating and developing a branch of physics called acoustic. So we can "stole" their results to serve our scopes.

The formula we need is the one in the first pic. Here is the meaning of various symbols:

- L is the length of the tube
- v is the speed of sound
- f is the frequency

Fine. Now we need to determine which notes we want to produce, and their frequencies. I'm going to make a full octave pan flute, so I need 13 tubes: C, C#/Db, D, D#/Eb, E, F, F#/Gb, G, G#/Ab, A, A#/Bb, B and C again. Each tube will produce a note a semitone higher than the previous one and a semitone lower than the next one.

Since it's is too generic saying "I want to play an E", we must specify also the octave. In my case the first C is a C4 and the last C is a C5. This make the A an A4, with a frequency defined to be 440 Hz (modern concert pitch). From this we can determine all other frequencies using the second formula (second pic, obviously). The n is the number of semitones between the note we want and the A4. If the note is lower than n will be negative, if the note is higher it will be positive.

Jonas.B says: Jun 26, 2012. 8:49 AM
Superb instructable! :)
I have one question though:

On wikipedia the speed of sound in room temperature is said to be 34320 cm/s, but when i check your calculations, it seems the used number was 33150 cm/s. Which one of us calculated wrong?
Drako84 (author) in reply to Jonas.BJun 26, 2012. 10:10 AM
Thank you!

I think none of us calculated wrong, simply because the speed of sound depends not only on temperature, but also on a lot of other things, for example on altitude or density of the air. Since the pan flute cannot be tuned once made, you must adjust the blow speed and force to raise or lower the frequency.
psycho banana man says: May 17, 2011. 4:50 PM
Very good and educating instructable!! Thanks!!!

One advise: Maybe it would be "safer" to cut the tubes a little bit longer (a few mm). Then, using the needle file and a good tuner you can tune each tube at the exact pitch. ;-)
ComplacentBard says: Apr 4, 2011. 9:48 AM
I think you meant physicist, not physician.
Daftehh says: Mar 8, 2011. 7:53 PM
One more thing added to my to-do list
also, you could use epoxy to bind the tubes together
arami says: Nov 17, 2010. 8:24 AM
Great place to start for making wind instruments! I would like to point out that physicists (not physicians) are the ones that acoustics... But other than that, great basic explanation on how pan flutes work.

Thanks :)
trubshac says: May 29, 2010. 2:54 PM
Brilliant instructables.  I like the theory as well as the practical explanation.  We've just made one out of the plastic coated mild steel handles of 3 floor brushes that we got from the poundshop!
Our first attempt just used insulating tape to close one end of the tubes - this didn't work at all.  We then tried stiff cardboard held in place with insulating tape which worked perfectly.

AndyGadget says: Jan 16, 2010. 6:43 AM
Neat Instructable, but a video of you playing them would really add to it.
I only found out recently that the way they're played in the Andes is for two players to blow alternate notes on the pipes, so each player is only playing half the tune with the notes bouncing back and forth between them.
Thank you! Well, I haven't posted a video mainly for 2 reasons: videos my camera can take have a very poor quality; and I'm not so good in playing...
After all, Stradivari was an excellent violin maker, but a poor violin player.

The way Andes performers play their instrument is very interesting, I'd like to see them in action.
Good point about Stradivarius.  I've never seen a video of him playing anywhere ;¬)
I can't find a video of the alternate blowing either.  We get a few Andean bands busking in the High Street during the year and one of them explained and demonstrated the technique once.  Since then I've seen others do it.
Doctor What says: Jan 16, 2010. 8:39 AM
Lovely!  My family used to participate in Renaissance Faires (well, they still do, but I don't!).  Using instruments was incorporated heavily into our character designs.

My stepmom played the fiddle and a mouth harp.

My dad played the Tabor Drum, the fife, the flute, and a dozen other random instruments.

I also played the flute.  (I liked juggling better than musical instruments)

We performed with an Irish Stepdancing group.  It was quite fun!

This would be great for those who can't find a pan flute.  (I'm also excited for your tin whistle!)

Very nice job!
Drako84 (author) in reply to Doctor WhatJan 16, 2010. 9:17 AM
Great! Renaissance Faires! I love them!
Sadly, I've seen only one... and desolate...

However, I hope I will not make you wait too long for the tin whistle. Stay tuned!