By the mid 1970's (c1976) the headstock logo design changed to a gold 'Martin style' decal that said, 'Sigma Guitars' in script with 'Est. On right-handed models while playing a Sigma guitar the 'sideways M' becomes 'right side up' suggesting 'M' for Martin. While retaining the same early logo for several more years (c1975/76) the peghead itself began to take on a more tapered shape by 1972. The sigma symbol is often described as a 'sideways M.' The early 70s models (1970 -1975) can be distinguished by a more squared peghead, shaped similarly to that of a 'spatula.' The logo consisting of a gold decal with the single word in block lettering SIGMA surmounted with the Σ symbol (the Greek letter sigma), in mother of pearl. Sigma guitars made in Japan from 1970 through 1983. Look in the soundhole toward the neck to see where this is etched. A Martin Guitar will have the model designation and the serial number etched on the neck block. Type sigma guitars in the search box, it's a long thread. The best website for info on sigma's is a folk music forum. 81XXXXXX.) Since we know these instruments were manufactured from 1984 through 2007 in these two countries, it is safe to assume that a serial number beginning with 81XXXXXX was not produced in 1981.
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#How to read martin guitar serial numbers serial numbers#
Serial numbers for Sigma guitars built in Korea and Taiwan are perhaps meaningless, though again some seem to indicate the year of manufacture (e.g. Here is a link with a demo recording I made using the guitar and some pics. Hi I bought an used Sigma-Martin guitar from a friend becouse it sound beautiful! The model is CG- 1ST or CG-IST (it s dificult to read) and serial number is: 99090007 - Made in Korea. On my Art primes, the s/n is located on the barrel along the back edge of the manual focus ring and just to the right of the focus-scale window. Sigma serial numbers are hard to read, as they have low contrast and very small font size. Awesome, that makes a lot more sense to me.