For the purposes of a pun, "cans" are another word for "headphones".
Here's how to make audio-cans from soup-cans, and some other things.
Step 1: Parts & Tools
Two large soup cans (Lidl chicken, vegetable & pasta - it's OK)
One Scotch Broth can (Lidl, better than OK)
Two small speakers (4 Ohm)
A wire coat-hanger
Electrical insulating tape
Various bits of wire
Expanded polystyrene foam
Most of the electrical content came out of an old phone I bought a while ago.
A knife blade
A soldering iron