Questions: Significance of Q

by Brian Burns

Originally published in American Lutherie #86, 2006



John Belluci of Baltimore, MD asks:

Please explain what “Q” is when referring to wood or instruments. The definition I’ve seen is, “internal damping.”


Brian Burns of Fort Bragg, CA responds:

“Q” is one of the basic qualities of the materials we use to make stringed instruments. The traditional low-tech Q test is to listen to the tap tone of a piece of wood and hear how long it takes for the sound to die away. The longer the tap tone lasts, the higher the Q, and the greater the potential of that piece of wood to make a loud instrument with long sustain. The design and construction of the instrument of course determine the ultimate result; the Q test just gives you an idea of the potential of that particular piece of wood.