Posted on April 21, 2023March 5, 2024 by Dale Phillips Battery-Powered Instrument Amplifiers Battery-Powered Instrument Amplifiers by Joseph Ennis Originally published in American Lutherie #69, 2002 and Big Red Book of American Lutherie Volume Six, 2013 After reading Francis Kosheleff’s description of building speaker enclosures which resemble instrument bodies, I thought I would offer my experience of what has worked for me. I have added battery-powered amplifiers and speakers inside instrument bodies to either augment the sound of a weak instrument like a harp or mandolin, or just to act as stage monitors. The thing left unspoken in Mr. Kosheleff’s article is that not just any speaker will work well. The speaker should be chosen to match the instrument body resonance. The first air resonance of a hollow body instrument is essentially the same as the Helmholtz resonance of a tuned speaker cabinet. The same math applies. The formula is given below. 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 April 21, 2023March 5, 2024 by Dale Phillips The Two-Storey Dulcimer The Two-Storey Dulcimer by Roger Alan Skipper Originally published in American Lutherie #101, 2010 I read John Calkin’s “Dulcimer 101” in AL#98 with interest, but with little expectation of practical application. I’ve never built a dulcimer; I’ve never wished to build one (sung to the “Purple Cow” jingle). Within a month, though, my best customer and great friend Dr. Gerry Snelson asked me to do exactly that. Perhaps anticipating my reluctance to regress to such a basic instrument, Gerry came armed with photos of high-end dulcimers, video clips of accomplished players, and with his normal bundle of challenging demands and fresh ideas. 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 April 21, 2023March 5, 2024 by Dale Phillips Calculating Soundbox Volume Calculating Soundbox Volume by Dave Raley Originally published in American Lutherie #70, 2002 and Big Red Book of American Lutherie Volume Six, 2013 Want to design a new guitar shape and maintain an equal volume of enclosed air by adjusting the height of the sides? Here’s how to calculate volumes. Accuracy is a function of how long you want to spend measuring and calculating. Consider two bodies: Figs. 1a and 2a. The body in Fig. 1 is 18" on the X axis and 4" on the Z axis. Suppose that you wish to make the body in Fig. 2 have the same volume as the body in Fig. 1 while maintaining the same X axis. Fig. 3 defines the axes regardless of the way the figures are turned. 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.
