Work Page 8-21
1960's Valco Resophonic Guitar 

VALCO The National String Instrument Corporation was registered as a California based company by John Dopyera in 1926. Within three years Dopyera would resign from National leaving ownership and management to his partners and form the Dobro company. By 1935, Dopyera had returned in a merger that formed the National-Dobro Company. With a steadfast mission to amplify the volume of fretted instruments, the company’s early focus was production of acoustic resonator guitars, but by 1935 National marketed their first electric guitar under the brand name of Supro. After a move to Chicago in 1936 the company changed the brand name to Valco. Over the following years Valco would manufacture electric instruments and amplifiers for other companies as well as their own. Valco is credited with many innovative firsts in electric guitar manufacturing including the first double pickup guitar, a reinforced neck that dispensed with the neck heel, and a molded fiberglass resin body branded by Valco as Res-O-Glas. Pigmentation could be incorporated directly into the resin allowing the body to be molded and colored in one step. The Val-Pro models all shared the same body design roughly mirroring the map outline of the United States. By 1968 bankruptcy would dissolve Valco, though the National name would resurface in the 1970s in the form of inexpensive Asian imports sold to the American market. 1988 saw the reintroduction of National in the form of the California based National Resophonic Guitars.
Sound clip (6 string cutaway)
You Tube

Convert from 6 string to 4 string tenor
22" scale
Single cone resonator/biscuit bridge

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