The Harptone company was a commercial successor to the Felsberg Company (circa 1893). During the 1930s, Harptone was more known for musical instrument accessories, although a few guitars were built between 1924 and 1942.
In the 1960s, The Harptone Manufacturing Corporation was located at 127 South 15th Street in Newark, NJ (07107) and Harptone's main guitar designer at the time was Stan Koontz (who also designed Standel and his own signature guitars). Harptone's guitar product line consisted of mainly flattop acoustics, electric archtops, and electric basses. Harptone instruments were built between 1966 and the mid-1970s when the company went out of business.
When Micro-Frets closed operations in Maryland in either 1974 or 1975, the company assets were purchased by David Sturgill. Sturgill, who served as the company president of Grammer Guitars for three years, let his sons John and Danny gain access to leftover Micro-Frets parts. In addition to those parts, they had also purchased the remains of the Harptone guitar company. The two assembled a number of solid body guitars which were then sold under the Diamond-S trademark. Unfortunately, that business venture did not catch on, and dissolved sometime in 1976. For further information regarding Harptone electric models, please refer to the Blue Book of Electric Guitars. Company history courtesy Tom Wheeler, American Guitars.
Guitars previously built in Newark, NJ between 1966 and the mid-1970s.

HARPTONE Acoustic Guitars Models

HARPTONE EAGLE (E-6) Image

HARPTONE EAGLE (E-6)

- dreadnought body style, Sitka spruce top, arched mahogany back, mahogany sides (curly maple back and sides were optional), round soundhole, ivoroid top and back body binding, 20-fret rosewood fingerboard, double truss rod, three-per-side...

HARPTONE LARK (L-6) Image

HARPTONE LARK (L-6)

- jumbo body style, Sitka spruce top, mahogany back and sides, round soundhole, ivoroid top and back body binding, 20-fret rosewood fingerboard, double truss rod, three-per-side Grover tuners, black pickguard, rosewood pin bridge, available...

HARPTONE PIONEER (P-6) Image

HARPTONE PIONEER (P-6)

- jumbo body style, Sitka spruce top, arched mahogany back, mahogany sides, round soundhole, ivoroid top and back body binding, 20-fret rosewood fingerboard, double truss rod, three-per-side Grover tuners, black pickguard, adj. rosewood bri...

HARPTONE RENZI 100 Image

HARPTONE RENZI 100

- nylon string, Alpine spruce top, round soundhole, mahogany back/sides, 19-fret rosewood fingerboard, hand-engraved headstock, rosewood bridge, three-per-side German tuners, available in Natural finish, 25.625 in. scale, mfg. 1966-mid-1970...

HARPTONE SULTAN (S-6NC) Image

HARPTONE SULTAN (S-6NC)

- single cutaway jumbo body style, Sitka spruce top, curly maple back and sides, round soundhole, dark top and back body binding, curly maple neck, 20-fret rosewood fingerboard, double truss rod, three-per-side Grover tuners, black pickguar...

HARPTONE ZODIAC (Z-6) Image

HARPTONE ZODIAC (Z-6)

- dreadnought body style, Sitka spruce top, rosewood back and sides, round soundhole, ivoroid top and back body binding, 20-fret bound rosewood fingerboard with pearl block inlays, double truss rod, MOP headstock inlays, three-per-side Grov...