The character of each instrument is initially defined by the wood from which it was made. It’s an aesthetic, as well as tonal choice. It’s also where the magic of being a luthier truly lies, as no two pieces of wood are exactly alike. This wide variation, even within a single piece of wood, is a persuasive argument for the attentive luthier, taking his time to create each guitar as an individual.
I’ve used Sitka spruce, German spruce, redwood, sinker redwood, and mahogany as tops before. To my ear, and the way I like to tune a top, however, there is no substitute for Adirondack spruce.
While all Adirondack spruce is red spruce (Picea rubens), not all red spruce can rightly be called Adirondack. The particular spruce I use is old growth, and harvested at a high elevation in the Adirondack mountains, giving it the specific physical properties required for a first-class guitar top.
Part of what makes Adirondack spruce special is its very high strength-to-weight ratio, and superb stiffness. This allows a top built to true 1937 Martin specifications, with no compromise in design.
There is more grain variation in Adirondack spruce than the more homogeneous Sitka. I select tops with an emphasis on being perfectly quartered, as indicated by the high amount of “silk” figure in the grain, and with no grain runout within the piece.
All the bracewood within the guitar is also Adirondack spruce, with the exception of the maple bridge plate, of course.
Backs and Sides
The back and sides of a guitar comprise its rim. Not only is the rim an acoustically reflective surface for the energy produced by the top, it’s also a key ingredient in the color and shape of the guitar’s overall tone. Like most luthiers, I use mainly either rosewood or mahogany for the back and sides.
For mahogany, I use what is often referred to as Honduran mahogany, big leaf, or “true” mahogany, Swietenia macrophylla. Most of the commercially available stuff these days comes from Brazil or Peru, and is of very high quality. I have little trouble finding very well quartered, even grained, light and stiff mahogany.
The selection of vintage-grade rosewood is indeed more of a quest. While Brazilian rosewood is considered the Holy Grail of rosewoods, what is available today is often of questionable origin, rarely quartersawn, and poor in quality. When I do build with Brazilian rosewood, I only use the best, and I do have a small selection of old, quartersawn, pre-CITES sets available.
To find a viable replacement for Brazilian rosewood, I began by studying the wood used by Martin in the 1930’s. Nearly without exception, it was relatively lightweight, strong, even grained, perfectly quartered, and had no runout. I have used several species, all genuine rosewoods, belonging to the genus Dalbergia, with great success. The key comes down to paying careful attention to the grain structure and orientation of any given piece, then building the guitar to reflect the individual character of that piece.
At the moment, I have some high altitude grown Costa Rican cocobolo, cut perfectly on the quarter well over a decade ago. It’s even grained, stable, and builds a bold and sonorous guitar.
I’m always on the hunt of special rosewood. If you’re interested in discussing the different species, what’s available, or general thoughts about tonal colors, drop me a line.