Posted on August 1, 2022May 27, 2025 by Dale Phillips Questions: Significance of Q 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. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
Posted on March 14, 2020May 26, 2025 by Dale Phillips Letter: Beam Stiffness vs. Strength Letter: Beam Stiffness vs. Strength by Fred T. Dickens Originally published in American Lutherie #41, 1994 Dear Sir, Please allow me to attempt a termination of the continuing misunderstandings originating with Mr. Ervin Somogyi’s interesting but flawed lecture given at the ’92 conference in South Dakota and perpetuated by its subsequent transcription in the GAL Journal and the letter in American Lutherie #39 from Mr. Dave Schwab commenting on the matter. The issue has to do with using the terms “strength” and “stiffness” interchangeably when discussing the mechanical characteristics of beams used as braces in guitar sounding boards. Both strength and stiffness of beams are important characteristics and depend on properties of the materials from which the beams are constructed as well as the physical dimensions of the beam. Both stiffness and strength of beams may be calculated using formulas which only require a knowledge of the material properties and physical dimensions. Those so inclined will find a very readable account of these formulas in Understanding Wood by R. Bruce Hoadley, ISBN 0-918804-05-01. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
