Laser Pen Sound Visualiser

In this guide you will discover how to make your own sound visualiser with simple resources. Allowing you to see a visual representation of sound, music or whatever you can plug into a speaker!

PLEASE NOTE - This guide does use a laser pen which can cause serious eye damage if used improperly, so please use with care.

• Laser Pen
• Speaker
• Sound Source (e.g phone, laptop etc.)
• Cling film
• Rubber Band
• Mirror fragment (mirror ball, old CD)
• Double sided tape

Begin by wrapping the clingfilm over your speaker to create a seal. Depending on the size/shape of your speaker you may need to place it into a bowl and wrap the cling film over the bowl.If you don't have clingfilm you can use a balloon, swimming cap - anything stretchy that will create a seal. I used a rubber band to keep the clingfilm in place, you could however use a cable tie as an alternative.

For the reflective element (which we shine the laser onto) I used fragments from a cheap mirrorball and stuck them on with double sided tape. However, you can also use the mirror section from a blank CD/DVD.

Where you place the mirror fragments is important to the shape of the projection, so try and place it as centrally as possible. But don't be afraid to experiment with different placements once all setup.

Plug your sound source into your speaker, for my video I was sending sound from my computer with a 3.5mm cable into my speaker.

How you arrange your laser and speaker will affect where the projection ends up in your room. At this point it is incredibly important you are careful with the laser and avoid your eyes. Depending on the strength of your laser it could cause serious damage.

You will need something to hold the laser pen in place, I use a set of 'third hands' to hold mine, however you could quite easily balance it on some books and tape it down. In my experiments I found that the more acute the angle is the more round your projected shapes will be. As the angle between the laser and speaker surface gets more obtuse the projection stretches into a thin line with not much horizontal movement.

Once the pen and speaker are setup as you like, you can begin playing the sound and et voila - you're visualising sound!

In my experiments I found lower/bassier sounds 'visualised' better - however volume also made a big difference as louder sounds 'excited' the clingfilm, and therefore the mirror, more. This is because more air is moving and pushing the cling film back and forth.

To make my music video I simply turned off all the lights and used my phone to film. You may notice it looks different in footage to in person, and this is to do with cameras working different to human eyes.

For a better explanation of this, scientist Steve Mould has a fantastic video where he explains what's happening.