Project Name — Straw Horn

Manufacturing Musical Instruments

Design Brief: To design and make a horn.

Context: When vibrating air changes the tone by an octave, this means that the air is vibrating twice as fast as before. Therefore, the air vibrates twice as fast in the open straw as the closed one. Also, the shorter the column of air, the higher the higher the sound it makes because air vibrates faster in a shorter straw than in a longer one. This is why the pipes in a church organ are different sizes. The small pipes make the higher sounds while the thick, tall pipes make the deep bass sound.

Possible Solutions: Examine musical instruments and discover how they work and design a horn based on these principles.

Design Considerations: List all of the things you had to consider for this project. Ensure that your design considerations are strong and fully developed.

Detail Design: Obtain a drinking straw from Mr. Ferguson and flatten one end of it. Using a pair of scissors, cut a taper ¾” long from one end of the straw. Put the tapered end into your mouth and blow through it. If you do not get a sound, keep the cut ends together with your tongue and try blowing again. Try touching the tip of the straw with your tongue as you are blowing. Feel the straw vibrating? This vibration is creating the sound.

Now, experiment with your straw. Cut a sharper taper into the end of your straw and blow it again. The horn’s tone will have changed. The ends are vibrating differently than before. Now, cut an inch off the other end of the straw. What happens to the tone now? Using tape, attach another straw to the end of your horn. What happens to the straw’s tone now?

Materials: 2 straws, scissors, tape.

Commissioning: Were you successful in this project when you tried it out?

Evaluation: Did this project work as you expected it to?

Reflection: Did you enjoy this project? What were you most proud of? What would you do differently next time?