By Dana Bourgeois
Q: How long should it take to break in a new guitar? Do you know of any shortcuts? —James Becker, Loveland, Ohio
A: Numerous and complex elements contribute to breaking in a guitar. After years of exposure to oxygen and UV radiation, wood undergoes chemical and structural transformations. Sound-damping compounds such as sugars, oils, pitches, and resins slowly become gasses and crystalline residues, allowing wood to vibrate more freely. Evaporative finishes, such as lacquer and varnish, go through analogous changes. Prolonged exposure to air and light causes plasticizers to gas off, molecular chains to morph, film thickness, and mass to diminish. After years of curing, older finish becomes a more efficient transmitter of vibrational energy.
More than just chemistry happens under the hood. A guitar starts life as 30 or so individual pieces of wood, each with its own moisture content, internal tensions, and structural “memory.” Glue them together and, initially at least, you get a guitar that still wants to be 30 pieces of wood. Over time, though, a guitar responds to forces that bear upon it.
Loaded under 175 pounds of string tension and subjected to regular vibrational movement, wood fibers begin to loosen. As internal tensions relax, volume and sustain increase and bass response strengthens. After longer periods of loading, wood fibers eventually stop stretching. Physical distortions become permanent, as evidenced by that “belly” behind the bridge of an older guitar that no longer goes away when strings are slacked. A permanently distorted top is stiffer in central areas than it was when new and flat, and more closely resembles a coaxial speaker: Localized stiffness enhances treble response (think tweeters), while looseness around the perimeter favors bass response (think woofer).
Different guitars break in at different rates. A guitar made entirely with well-seasoned woods, constructed in a stable environment, expertly finished, and designed to flex and distort in ways that favor a full range of frequencies, will break in more quickly than one made with improperly or inconsistently seasoned wood, assembled under inconsistent climate conditions and over-rigidly constructed.
Though the break-in process can continue for years, rate of change slows exponentially. Happily, most contemporary luthiers employ a variety of techniques for coaxing guitars to sound partly broken-in from initial string-up, including use of cutting-edge wood-curing methods and/or torrefied woods, sophisticated finishes and application processes, high-tech or at least well-monitored climate controls, and advanced knowledge of acoustic design. A new guitar from a reputable luthier should begin to sound and feel quite comfortable after a year of good playing.
But breaking in still requires playing. A pristine, unused vintage guitar can radically improve with regular playing, suggesting that chemistry alone cannot create an authentic vintage sound.
While vibration of any kind may benefit a very new guitar, I am personally skeptical of most break-in strategies that don’t involve real players. It’s difficult to imagine how responding over and over to a device that artificially excites strings at a single frequency can cause a guitar to develop a balanced, musical voice. Of equal concern is the potential for unintended consequences after exciting a guitar over long periods with randomly or algorithmically generated frequencies, or, for that matter, even with amplified music.
Any guitar favors certain frequencies over others. The name of the game is maintaining—rather than enhancing—stronger frequencies while developing weaker ones. This happens, consciously or unconsciously, when a real player playing real music avoids overplaying certain notes and puts a little something extra into others.
Qualified observers have long speculated that guitars played for many years by exceptional players often develop, rather than start out with, exceptional voices, in good part because of how they are played. Indeed, when playing certain guitars I sometimes sense the spirit of a current or former player from the sound, response, and feel of the instrument.
Though the proposition is difficult to prove scientifically, I don’t doubt its truth for a New York minute.