Great Acoustics: Alan Carruth’s “Proper” Harp Guitar

This article first appeared in the February 2011 issue of Acoustic Guitar.

One day, almost 10 years ago, Alan Carruth was attending the “Dangerous Curves: the Art of the Guitar” exhibition at the Museum of Fine Arts in Boston, Massachusetts, when it occurred to him that the term “harp guitar” was a misnomer. His reasoning had to do with the way the strings activate the instruments’ tops: a concert harp’s strings pull obliquely on the soundboard, but on most harp guitars, the strings are parallel to the soundboards. In actuality, the “harps” on these instruments function as bass zithers.

Since 2000, Carruth has built several harp guitars in his Newport, New Hampshire, shop. His most recent (shown here), which he debuted at the 2010 Montreal Guitar Show, is an exercise in thriftiness. In December 2009, the Musical Instrument Makers Forum (mimf.com) started a $100 Acoustic Challenge, inviting luthiers to make instruments using less than $100 worth of supplies, starting on Christmas day and finishing by mid-March. For the project, Carruth came up with a “proper” harp guitar, based on his standard classical/00-size model (14.37 inches wide at the lower bout), and using a 25.59-inch scale for the standard guitar neck. Carruth created a separate soundboard on the harp, connected at one end to the guitar’s bass-side upper bout, and at the other end to the headstock, and arranged perpendicularly to the strings.

To keep things on the cheap, Carruth made the top from Sitka spruce that Martin Guitars had donated to Carleen Hutchins (the late violin maker) for research purposes in the 1970s. Carruth made the back and sides from some inexpensive padauk, which he considers to be an excellent substitute for Brazilian rosewood. These woods give the harp guitar, intended for Celtic music and fingerpicking, a sweet, round tone. 

Both sets of strings enhance each other’s sound. The guitar has an uncommon resonance and complexity, thanks to the harp’s extended arm, soundboard, and back. And the harp receives energy from the guitar, producing overtones on the drone strings, the guitar in turn benefitting from a smooth attack and reverb-like sustain.