Good Vibrations

What an amazing video:

Anyone who’s played a harmonic on the guitar knows that string vibration is a magical, mysterious phenomenon. I’ve heard it compared to a moving passenger train. As the countryside flies by, your teacup is rattling on your saucer: That’s one kind of vibration. But the whole traincar is vibrating too: A second vibration. The traincar is also swaying as it moves: a third vibration. And the entire train is coursing through s-curves in a winding valley: A final, huge vibration.

In the same way, a plucked string has many different layers of vibrations happening simultaneously: The whole string is moving side-to-side, which creates the fundamental tone that our ear is drawn to. But smaller vibrations—the traincar and teacup vibrations—create overtones that are hard to pick out, but without them our plucked guitar strings would sound more like electronic beeps.

What blows me away in this video is how huge those “teacup” vibrations are. I figured they were tiny, humming wiggles, barely perceptible even if we could slow them down. But apparently, our strings wiggle like sidewinders. Incredible.

Incidentally, if you’re interested in trying to hear those subtle overtones in your guitar’s notes, play a harmonic on a string, then pluck the open string. Listen for the sound of the harmonic quietly ringing behind the loud fundamental pitch.

Comments 13

  1. oracle

    This is not indicative of how guitar strings vibrate at all. The effect is caused by the delay of the rolling shutter in the iPhone. A guitar string is much to taught to “wiggle like sidewinders.”

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  3. Trevor Birch

    Hi Rob and All
    You are right it is an amazing video, however I have to agree with ‘Oracle’ that it is “not indicative of how guitar strings vibrate”. The fingerpicking guitar piece is fantastic and I enjoyed listening to it but the fact that I could hear it is because the video has not been slowed down. Because the string vibrates at the same frequency as the note it is producing when we slow it down enough to see the vibrations the tone falls below the audible.
    To see how a string does vibrate in slow motion it needs to be recorded at a high speed and played back at normal speed. The video here http://www.youtube.com/watch?v=6sgI7S_G-XI&feature=related demonstrates this. High speed cameras do not record sound so the soundtrack to this video is dubbed and in my opinion nowhere near as nice as yours.
    The relationship between pitch and vibration can be heard when a train passes by and the pitch of its horn decreases as it vanishes in the distance. This is known as the Doppler Effect and it is used by the police to detect speeding vehicles.
    I really like your site and I do think your hard work was worth it.
    Regards
    Luckytrev

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