Transient Vibration of a Guitar String

Dr. Thomas Huber

Gustavus Adolphus College

Description

To make the scan below, the new Polytec PSV-400 scanning laser Doppler vibrometer at Gustavus Adolphus College was used.

An acoustic guitar was excited by a 4 millisecond long "tap" from a mechanical shaker that struck the D-string to simulate a single string being plucked. The velocity of the string was measured using a Polytec PSV-400 scanning laser Doppler vibrometer. For this measurement, there was a capo on the 6th fret, just out of the field of view of the photograph and vibrometer measurement. The video shows the first few reflections as the wave bounces back and forth along the string.

 
 
 

Technical Details

 
Photograph showing Washburn guitar with a mechanical shaker that was used to tap the string