How to Listen to Light

Step 8 LED "tea light" candles play music for some reason

Seriously.

Just place the light sensor near the LED candle and in many cases you'll hear cheap electronic music coming out the amplifier. The one in the picture below plays "Fur Elise".

It is also possible to tap into these little LED candles and listen to the music via wire, as shown in this instructable:
http://www.instructables.com/id/Listen-to-a-led-tea-light/

I suspect that the reason for this is that those mass-produced music chips also work well as a source of time varying "flicker". That is, this signal looks like flickering light when driving an LED. The same signal sounds like cheap electronic music when driving a speaker. The same chips are used for both, or at least that's what I suspect. If anyone can confirm this hypothesis via a source in the Chinese knick-knack industry, please comment.

Comments

[rcisneros]

Actually you are half right.
They are prob using the music chip as a template that produces a smooth flicker cycle they have tons of.
The second part is because our brains naturally like certain sounds, patterns and tones. We change them over time, but there is a larger portion of these tones and patterns in classical music. I believe Bach is the winner in that category.
In that way flicker would cycle would be more pleasing.

[robcull]

Fur Elise??

Really?

Can you post a video recording of this sound?

[Jack A Lopez]

For those of you who asked for sound samples for the "How-to-Listen-to-Light" 'ible, I have added a last step with a number of .wav files attached to it.
(http://www.instructables.com/id/How-to-Listen-to-Light/#step9)