The Dobro - A Reso What??

reprinted with permission from Jerry Pendergrass

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A RESO "PHONIC" GUITAR!! THAT'S WHAT. Its daddy was a standard old flat-top guitar laid across the knees and played with a bar. If you want to know who invented the thing you're Simply Out of Luck. Theories abound when it comes to "who" started playing a guitar in that fashion. And each theory has its incorrigible followers. As far as I'm concerned, no one has ever definitively solved the mystery. One thing is certain however, it's a recent invention about a century old. The best known story, of which the details seem to vary with each telling, is of Joseph Kekuku. Following, are two of the most haggard variations linked to this Hawaiian fellow. One story has him accidentally dropping his comb on the strings of his Spanish guitar; the subsequent sliding sound that the comb produced caught his attention. The other story claims that he dropped his Spanish guitar while walking along a railroad track. As the guitar slid face down off the rail it made a conspicuous sliding sound. I once (and only ONCE) dropped my guitar face down on a sidewalk. I don't know how you'd react, but I darn sure wasn't concerned with the sound that it made!!

This next one adds a bit more color to the comb story. As a youngster, Joseph would frequently accompany his cousin, who played violin. He became captivated with the smooth slides that his cousin could produce on the instrument. Kekuku first tried a comb, and then later a glass in an attempt to duplicate the slides produced on the violin. Apparently he didn't continue, simply discarding the experiments. But later in life, he accidentally dropped his comb (must have had well groomed hair) on the strings of his guitar, reminding him of his earlier experiments. Following that incident, a friend supposedly handed him a gift while he was playing the guitar. Upon opening the present, a pocketknife fell out and landed on the guitar strings. The occasion prompted him to utilize a steel bar for a better sustained sound. What can one conclude from these stories? The only thing I can deduce, is, that Kekuku was very clumsy around a guitar.

Though we don't know who invented the "slide guitar" we surely know who it was that invented the contemporary "resophonic guitar". John Dopyera developed the first tri-cone resophonic guitar in California during the early 1920's. The three resonator cones were connected together (or bridged) at their centers by a T-shaped bar. The headstocks were rounded but peaked in the center. National was the brand name under which they were sold, and those who played Hawaiian music preferred the square neck National tri-cone. A single cone resonator, that had the bridge resting on the tip of the cone, was later created. Also produced under the National name, the guitar came in both wood and metal construction. Elaborate engraving or colorful Hawaiian scenes were applied to some of the metal guitars. Later instruments had headstocks that were flat across the top instead of rounded. Initially the peg head was slotted, but according to John Dopyera a solid peg head was later used.

No longer with National, John and brother Rudolph invented a new type of resonator cone in 1928. Still a single cone type, the resonator was bridged with a strong aluminum "spider" that rested on the lip of the cone at its outer periphery. With pressure absent from the center of the cone (as in the older style) and instead distributed at eight points around the edge, a clearer tone with more sustain was possible. Using this cone, the brothers produced a wood body guitar under the trademark--Dobro.

The name "Dobro" is an abbreviation derived from the first letters of DOpyera BROthers. The cover plate and sound hole design are suppose to resemble the Dobro logo.

The three holes in the guitar body, just below the neck represent the three dots at the top of the lyre. The two screened holes on either side of the three holes, imitate the laurel shape at the upper left and right of the lyre. Use your imagination on the cover plate, strings, etc. The sound chamber, upon which the resonator rests, spans the gap between and is glued to, the back and top of the guitar. The resonator actually "nests" within this sound chamber. A resonator cone is made of spun (or stamped) aluminum and resembles a hi-fi speaker. Modern resonators are 10.5 to 11 inches in diameter, concaved, with a convex cone-shaped dome in the center. The eight-leg duralumin spider bridge, (the bridge on any instrument supports the strings) spans the resonator cone resting its legs around the edge. A long screw protrudes downward through the spider into the convex dome, securing the spider to the resonator. When a string is plucked, the vibration is transmitted through the spider to the edge of the resonator, it in turn vibrates, projecting the sound (similar to a speaker) throughout the instrument and also outward passed the cover plate into the air.

The Dopyera Brothers (you'll also see it spelled Dopera) also made other resophonic instruments such as the standard guitar, mandolin, ukulele, tenor guitar, banjos, etc., but nothing as popular as the Resophonic Guitar. Just as "Crescent" is synonymous with the adjustable spanner wrench, most everyone calls the resophonic guitar, a "Dobro."
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