While it was long believed that the serial numbers of Sigma instruments were of little use in dating the instruments (except on the DR-28N and DR-35N, which were assembled and finished in Nazareth in 1981/’82 using Japanese-made parts and marked “Made in USA”), today there is a basic understanding of how they work, based in part on the many factories that produced Sigma instruments.In 1983, the bulk of production was moved from Japan to South Korea, where the line underwent a huge expansion.In a 1979 brochure, these were duly delineated as the 7, 5, and 3 series; models with higher numbers were given higher-quality materials and more-attentive craftsmanship, as well as overall quality and quantity of appointments. Note the “spatula” headstock and Greek Sigma symbol logo.Its laminated-mahogany back and sides gave it a bright, warm tone. Made by Tokai Gakki, it had a great, percussive low-end attack and remarkable overall balance. In 1980, solid-top Sigmas were re-named numerically to correspond to the Martin model they emulated, and this was the top of the line.
However, if you are a player, I would recommend that you keep it as it will improve in value and tone as the years go by.
Where to find the serial number Look in the sound hole in the direction of the neck and you see on the neck block model and serial numbers are stamped.
Long overlooked and relegated to an obscure corner of the collectible market, Sigma by Martin guitars have recently gained popularity among a new generation of collectors.
except on the 12-string DR-12-7 – a fact that plagued Martin sales reps, who were advised to “convert” dealers to the DM-12-5.
Beginning in ’73, certain lower-end models were manufactured in Korea, setting a pattern of multi-country/multi-manufacturers that continued throughout the run.
I've since invested in having the nut and saddle replaced with hand carved bone, and the frets and neck fine tuned for light strings -- it plays so easy and sounds simply wonderful. I wanted to know how much it was worth, when it was made, all that good stuff. I hane no idea of quality( supposed very good), year,price,etc, It sounds very good but i think i'll use as a 6 strings.
Can u send me please some notes about this 12 strings?
Thanks Hi, you have a 12 string Dreadnought with mahogany back and sides. Some say that the first two or the last digits of the serial number denote the year of manufacture, but this is not reliable as Martin used different factories to produce their Sigmas. The best you can due is a bill of sale IF it's from the original dealer and it's a guess how long they had it for sale.
Good Luck : I have a Sigma DM 12-4 made in Korea, wiki says it after 1980, looking for year details etc, anything you can give would be appreciated.
The instruments employed economy-minded materials like laminated woods for their tops, sides, and back, but were generally well-constructed.
The initial batches had a zero fret, covered truss-rod access, and bridges with a saddle “elevator.” Roughly 20 models were offered; the classical instruments had slot pegheads, while the acoustic flat-tops were characterized by a flat headstock reminiscent of a chef’s spatula (and now nicknamed as such), with the logo consisting of a gold decal of the word “Sigma” surmounted by the corresponding Greek letter (∑) in mother of pearl.