Sigma guitar

Manufacturer	Sigma by C. F. Martin & Company

Guitar maker C.F. Martin & Co., based in Nazareth, Pennsylvania, created a line of inexpensive guitars in 1970 to compete with the increasing number of imported guitars from Japan and elsewhere. The result was Sigma Guitars.

The Sigma line was discontinued by C.F. Martin & Co. in 2007.

In 2011 the German company "AMI Musical Instruments GmbH" purchased the rights to the name and relaunched Sigma Guitars again, this time being produced in China.

Since the U.S. rights to the Sigma brand name and trademark had been allowed to lapse by C.F. Martin & Co. prior to selling the brand to AMI, and had since been picked up by St. Louis Music of Missouri, AMI is not allowed to use the brand name "Sigma" in the U.S. for their current line of guitars. They are distributed and sold in the U.S. as Kindred Guitars. The sole current U.S. distributor is now Six String Brokerage LLC, Nazareth, Pa.

Initial construction was in Japan by various manufacturers/factories from 1970 through 1983.

The first Sigmas were typically dreadnought acoustics, although Grand Concert Series (GCS) and classical models were also produced from the early 1970s (1971?) onward. Though other models were produced the most common two throughout the '70's were the Dreadnought models DM-5 (DM12-5) and DR-7 (DR12-7.) D for dreadnought, R for rosewood, M for mahogany and the number denoting the grade of wood, 5, 7, 9, 11, 15.

Construction moved from Japan from 1970–1983, to Korea from 1984-1994, to Taiwan in 1994 (made in both Korea and Taiwan for the 1994 model year) and finally Indonesia (?–2007).

In 1978, model designations were added to capitalize on Martin model numbers: the DM-18, DM-19, DR-28, DR-28H, DR-35, DR-41, and DR-45. They are called 'Second Generation' Sigma's by C.F. Martin and featured solid wood top. The "First Generation" DM-5 and DR-7 (laminate wood bodies and tops,) as well as other early models (e.g. GCS-7/CS-7) continued to be built during this time as well.

Pegheads & Logos

Sigma guitars made in Japan from 1970 through 1983.

Labels and Brands

Sigma's made in Japan from 1970 through 1979 used a paper label to identify the model and serial number of the instrument. The model and serial numbers were usually stamped on in ink, but some are known to have been hand-penned. This is especially true of unusual, special (sample/prototype models) and/or low production number models (e.g.: DT-30.)

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Wikipedia