Can Trumpet — The best use of a can before recycling

Hello! I’m Andy. I’ll be showing you a simple DIY instrument that is incredibly easy to make anywhere you are, and can also be played obnoxiously loudly. All you need is some kind of can, aluminum or steel, tall boy or normal soda can. You likely have one nearby you’re already sipping on, and you can follow this tutorial once you’ve finished it!

All the supplies you need for a DIY orchestra

Imagine this. It’s summertime. You’re in a park. There’s people playing frisbee nearby. You have just finished off the dregs of your favorite drink, held safely in an aluminum can. While you were sipping from your modern beverage container, you were also harking back to the drinks of the good old days. You miss the times when opera singers could resonate with and shatter their wine glasses with singing at glass’s natural frequency.

Unfortunately, you say to yourself, the same is impossible with the modern can. The metal membrane is grounded on both ends, and too supple to just shatter from just a voice. Besides, the outside can’t reverberate while the can is being held in your hand; you’ll just absorb the vibrations. Alas, you think to yourself, it is no longer possible to sing with drinks.

One tall boy of Yerba Mate, a drink exclusively consumed by college kids and Native South Americans.

But wait. What if there was some way to create a membrane that is still attached to the main structure of the can, but can vibrate independently of it? That would allow the can to pick up on vibrations in the air, and resonate like an antenna if the frequencies matched its natural resonance.

You bend in one side of the can near the top, and another near the bottom, so that a flat, rectangular membrane forms.

First bend at the top of the can, parallel to the mouth hole and FLAT with respect to the curvature of the can.

The membrane formed by bending in top and bottom segments of the can, illustrated in orange.

If the middle of the rectangle bulges up, just crease the vertical sides of the membrane to try and flatten it.Take care to flatten the membrane so that it isn’t bulging out. Otherwise, it won’t be able to pick up vibrations as well!

Now that you’ve made your instrument, it’s time to play it! There are a few resonant frequencies of the can, depending on how large of a membrane you made, so we have to check through experimentation.

First, purse your lips like you’re about to whistle, then bring the can to loosely touch your lips, being careful to leave room for airflow in and out of the can. Now, start singing any note into the can (at a normal conversational noise level), and listen to the sound. If it just sounds like you singing into a can, you haven’t found the right note yet. Keeping your mouth on the mouthpiece of the can, slide the pitch of your voice up and down your vocal range until you hear what sounds like an extremely brassy trumpet noise at a much louder volume than you singing into the can alone. That note is the resonance frequency!

An example of me playing the can. Sing first, then bring the mouthpiece to your lips. Vary the pitch to find the brassy notes.

Through practice, you can consistently hit this note, impressing your friends and colleagues. Beware: eventually the brassiness and volume of the can-trumpet gets on everyone’s nerves except for the person playing it, and it can be hard to notice when you’re having a lot of fun figuring out what other notes get amplified by your can instrument.

There are a few design choices that can be made, for instance adding more membranes or different shapes of membranes can change what notes get amplified. Have fun experimenting to find new variants, and enjoy your more musical lives!

Finally, remember to recycle the can when you’ve had your fun!

Andy