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From silly straw to annoying instrument

By David Shaw, 15 November 2018

Do you get annoyed when you get a plastic straw with your drink? Instead of throwing it out, take it home and use it to make a musical instrument!

You will need

• Plastic drinking straws
• Good scissors

Building the instrument

1. Take a straw and squash one end of it flat.
2. Cut the squashed end to a point, about 1–2 centimetres long.
3. Trim just the very tip off the point so it’s not so sharp.

Playing the instrument

1. Put the pointed end of the straw in your mouth, so the point is just inside your lips.
2. Curl your lips over your teeth and then push down on the straw.
3. Blow into the straw and release the pressure on your lips slightly. If you’ve got the technique right, the straw will start to play!
4. If you’re having difficulty, try:
   • blowing harder or softer,
   • pushing harder or softer with your lips,
   • moving the straw slightly further into or out of your mouth.
5. If you have a tough straw, you might want to gently bite the straw flat to make it easier to play.
6. Remember, practice makes perfect!

Improving your instrument

You can make a few different notes by blowing harder or softer. To make even more, you’ll have to modify your instrument.

1. Scissors method: Start playing a note, then cut a short piece off the end of the straw – the note should get higher in pitch!
2. Flute method: Cut small holes along the length of the straw. When you play, cover them with your fingers. Covering and uncovering the holes should give you different notes.
3. Trombone method: Find a straw that is slightly bigger than your instrument. Put the big straw over the small straw. Start playing a note, and then slide the big straw to make the whole tube longer or shorter – you should get different notes!

What’s happening?

Sounds are vibrations in the air that we can hear. A clap is just one pulse (and some echoes). A musical note is a continuous vibration, more like an ongoing vibrating phone buzz.

In this activity, the two pointy ends of the straw vibrate, causing waves in the air that we hear as noise. By blowing harder, we can sometimes get the vibration to go faster, which makes a higher note. But there’s more to it than that.

All objects react differently to different vibrations. Reflections and echoes inside that object mean that it will vibrate easily at some speeds, and at other speeds it won’t vibrate well at all. When the vibration works well, we say that it resonates.

When you’re playing your straw instrument, you’ll find it easier to play notes that resonate with the shape of air inside the straw. If you change the straw by making it longer or shorter, the vibrations that resonate will change, and the notes you can play will change too.

In general, slow vibrations require more space to resonate in, so if you want to play a low note, you’ll need a long straw. Quick, high pitched vibrations tend to work best in small objects and short straws.

Real-life science

This straw is a type of double reed instrument. It’s called that because it has two vibrating parts – the pointy ends of the straw – that vibrate next to each other.

In an orchestra, the oboe and bassoon are both double reed instruments. So if you enjoyed playing with your straw, you could consider trying one of those instruments!

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