The Coolest Way to Visualize Soundwaves in a Room

We all know that the speed of sound is slow enough that we can perceive a delay in some situations, such as the time between seeing lightning and hearing thunder. But we don’t normally get to experience that on a smaller scale. That’s why this project from HandicraftRecordBook is so cool: it lets you visualize soundwaves as they move around a room.

This set up is very clever, because it doesn’t require any complicated setup and it is infinitely scalable. It consists of many sound-reactive boards placed around a room. Each board has a set of LEDs that light up when it detects sound with amplitude over a specific threshold.

By arranging many of those — dozens or hundreds — around a large room, it is possible to “see” the soundwaves as they propagate and bounce off of walls.

Because this works best when there are a lot of boards, HandicraftRecordBook designed them to be affordable. They don’t require any microcontrollers and the most complex chip is a DC-to-DC boost converter, which pushes the voltage from a AA or AAA battery up to 5V. The microphone connects to transistors that switch power to the LEDs when sound amplitude is high enough (resistors set that threshold).

These are still soundwaves we’re talking about and they do move fast, so this whole setup works best in large rooms like gymnasiums. But with enough of these boards in a big enough space, you’ll be able to see the patterns of the soundwaves.