Friday, February 13, 2015

Monday, February 2, 2015

River Reflections - January

Our January Big Fishes

Design and Engineering - Sound

Michael shows the McGurk effect

At the beginning of this year, I had the pleasure of joining the River and Sky classes during their Engineering classes to talk about sound. We looked at different ways that sounds can tell us information about an object, even without seeing it.

Listening to pitch we were able to guess the size of a house cat, and by lowering the pitch we made it sound like an animal closer to the size of a lion. We also played with pitches of some of the students’ voices, making them sound like chipmunks and giants. We even played a sound so high, that the kids could hear it, but not the adults!

We learned to listen to volume and other clues to determine distance, and to use both ears to determine direction. We even demonstrated that humans have a rudimentary echolocation, like a bat.

I showed two sound "magic tricks." One was the McGurk effect, which (for most people) demonstrates that what we see can effect what we hear.

Lastly, I played two loud annoying tones simultaneously, which resulted in near silence. Because sounds are made up of waves, playing two identical tones such that the waves directly interfere with one another can neutralize both tones.

This piece was written by Michael Kraskin, a former composer, sound designer, audio engineer, and Lower School parent.