Make your own Slap-o-phone

They make great toys for playing rhythms and simple tunes. You can buy them for lots of money , or you can make your own by following these instructions.

You will need to buy a set of golf club tubes. These are available in most sporting goods stores. They're used inside a golf bag, to protect the golf clubs from banging into each other. They are about 1 inch in diameter and 36 inches long. Most I've seen are made of black ABS plastic, but there are also white translucent ones. The plastic is very light and easy to cut with scissors. In my area they cost about one dollar each.

Get as many as you want to make the scale you choose. There are lots of musical scales to choose from. For beginners, I recommend a pentatonic scale (five notes per octave), because almost any combination of notes will make a pleasing sound. Much of the music of Africa and Asia is pentatonic. Diatonic (eight notes per octave) and chromatic (twelve notes per octave) are also fine, if you want to get more complicated.

For each note in the desired scale, cut a tube to the appropriate length. I usually label each tube with its note, so you can find notes easily. Then start whacking. That's all there is to it.

Here are some basic scales.

Pentatonic	G3 A3 C4 D4 E4 G4
Diatonic	All naturals (no sharps)
Chromatic	All notes

Here is a table of musical notes and tube lengths.

Note	Freq	Wave	Tube	Tube
	(Hz)	(cm)	(cm)	(inches)
G3	196.06	350.39	87.59	34.48
G#3	207.73	330.71	82.67	32.55
A3	220	312.27	78.06	30.73
A#3	233.09	294.73	73.68	29
B3	246.95	278.18	69.54	27.38
C4	261.65	262.56	65.64	25.84
C#4	277.22	247.81	61.95	24.39
D4	293.71	233.89	58.47	23.02
D#4	311.19	220.76	55.19	21.72
E4	329.7	208.36	52.09	20.5
F4	349.32	196.66	49.16	19.35
F#4	370.11	185.62	46.4	18.26
G4	392.13	175.19	43.79	17.24

For the audio geeks, this table assumes the tube is a half wave resonator (open at both ends), with no end correction. Speed of sound is assumed to be 343.5 meters per second, which corresponds to typical atmospheric conditions at a temperature of 68 Fahrenheit. The notes are in 12 tone equal temperament, using the ASA octave notation (C4 is middle C).