DIY speaker

Paper cups can be loud!

15 minutes


  • Carefully review the general safety advice on the back of the box cover before starting the experiment.
  • Read the “Working with Batteries” section of the safety guidelines carefully before proceeding.
  • Do not let children under 8 years old handle small magnets.
  • Disassemble the setup after the experiment.

Step-by-step instructions

Phones without a headphone jack will require an additional adapter (not included in the set).

Assemble a stable stand and equip it with a coil to make the speaker work.


Let's turn a paper cup into a speaker megaphone.


In addition to the coil, the speaker will also require a magnet.


For better sound quality, the microphone must be connected to the amplifier.


Electric current has to pass through the coil for the speaker to produce sound. Apply the current from your phone by playing music from the app. If the sound is weak, bring your ear closer to the speaker.


To avoid having to strain your ears, connect the setup to the battery-powered amplifier.


Switch on the battery power to the amplifier and enjoy the music!



  • Dispose of solid waste together with household garbage.
  • Dispose of used batteries in accordance with local regulations.

Scientific description

Did you know that not only do we breathe air, we also hear through it? The speaker in your phone, for instance, is constructed very similarly to the design you just made.

The magnet  is positioned adjacent to and along the coil  with electric current  running through it and changing directions according to the pre-recorded diagram . This time, the magnet  is attached to the bottom of the cup , spurring it into vibrational movement along with the magnet.

The bottom of the cup  pushes the neighboring air , and the air’s movement is transferred further and further in a ripple effect. When these oscillations reach our ears , we perceive them as sound.

If you increase the volume on your phone, the bottom of the cup  will arch more dramatically and push the air  harder, creating sound waves of a larger amplitude and making the sound louder.

Curiously, we can hear sound underwater. It can propagate not only through air, but also through other materials and even solids!