Light Organ


We began by analyzing the frequency content of common songs to map each channel into an appropriate frequency range. Each channel features a band-pass filter and an envelope detector to output an analog voltage corresponding to how prevalent that frequency range is in the song. The analog voltage is then fed into an LED driver that lights a number of LEDs according to the signal strength relative to its full-scale. Our artistic choice was to lay out the LED channels in concentric rings in different colors on the board.

Given the amount of area we were allowed for the board and all the components required for all six analog filters the layout was quite a tight squeeze. After pains-taking hours of layout puzzles, we were able to get it done intelligently. This project was incredibly useful in developing my systematic debugging skills as well. For some reason it’s a lot easier for me to think of debugging systems piece-by-piece in electrical circuits, but since then, the mindset has expanded to all the engineering work I do.

In the Electrical Engineering Prototyping course at Olin, we learned the fundamentals of practical electronic circuit design, layout and fabrication. Over the course of the semester we had numerous lab exercises and design challenges that culminated in the design and simulation of a circuit then fabrication of the PCB. For my project, I worked with a partner to make an analog 6-channel “light organ” that responds to an audio input signal with patterns of flashing lights.



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Cambridge, MA 02139



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