With regards to Sterling Webb, and I do thank him profusely for the information he has provided, I must say that from my own personal experience I can not agree with all he has said. He should not take my comment as an insult because I too am aware how difficult it is to consolidate and verify information about these wonderful instruments. As stated, even Martin seems confused and will only offer "stock" answers these days. In fact I got a rather rude reply to a query I made about my guitar a few years ago.

I have often wondered if Sigmas were made by more than one Japanese company in those days which might explain the model and serial differences as well as other physical inconsistencies/ discrepancies?

Some personal history: From the time I was about 6 yrs old, I wanted to be a drummer and became one. However, while in college in Bethlehem, Pa. during the mid-'70's about 10 miles from Nazareth I began to realize that not everyone appreciated the drums, especially the girls, and that drums were much, MUCH harder to carry around than a guitar. So in short and having a few guitar playing friend's, I too took up the guitar.

My best friend had purchased a brand new D-18 around 1974, so he & I went to a local music store on September 23rd, 1977 to check out what was there and in my price range. In short, and knowing I wanted a 12-string, we decided a new Sigma DM12-5 was the guitar for me. $199.50 retail plus another $35.50 for a good hard shell case... which I still have BTW.

I'm sure the guitar had been there for at least 6 months before I bought it so it must have been a '76 or '77 model. The serial number was 017482. It had open-back tuners which have held up better than the frets over the years. It also had the Martin style headstock decal (Sigma Guitars/Est. 1970,) which Mr. Webb calls the second gen instruments beginning around 1980. Obviously this can't be completely correct.

And up till now, I always assumed it was a plywood guitar but it sounded so sweet and had decent volume too. I had removed the rear strap pin on many occasions and was never able to truly tell.

So about ten months went by and this instrument began to belly, badly! Being so close, I took it to the Old Martin factory (c1835) on North St in Nazareth (June 27th, 1978 to be exact) which was then being used as the "Import House."

One of their luthier's looked it over very well and even though I begged him, he said it simply was not worth fixing. He went to another room and brought out 3 brand new DM12-5's, fresh from their boxes and asked me if I liked any of them? If not he would get three more. I chose one and handed it to me and said, "How do you like that?"

I told him I was new to guitar but really liked the way the other was set up. So for the next 2- 2-1/2 hrs he tediously went over it and adjusted everything, occasionally handing it back to me for my approval. When I was satisfied, he installed a new set of Marquis strings for me (my chosen strings) and carefully put it in my case for me. "Here ya' go!" was all he said. I wish I knew who he was and where he is today. I would love to be able to thank him much better than I was able then. Nice guy, and very patient with someone who wasn't quite sure what he wanted at the time. I played that (2nd) guitar for over 30 yrs.

Fast forward to Sept 2009, the Friday before Labor Day. While at work, our home was broken into and three of my guitars were stolen... the three I played regularly (naturally,) among them the 12-string. I was heart-broken. 31 yrs of friends, parties, playing with friends and Gigs, all gone.

So I went in search of another 12-string and purchased what I think is a '79-'80 DR12-7. Pretty std stuff, except the "economy" tuners were bad so I replaced them. Also the bridge pins, saddle and nut were replaced w/bone.
A few weeks later I also purchased a 52SDR-9 which by and in all views seems to be made of solid woods!!

I've had it all apart, looked inside with an inspection mirror, etc and am still looking for further clues, but it has the 1st Gen Sigma headstock logo, beautiful rosewood 3-pc back and sides, non-adjustable bridge, no zero fret, interesting fret board inlays (not quite like snow flakes. More like a maple leaf in mirror image of itself.) single bound headstock and fretboard. Currently I am having a few frets professionally replaced and a bone nut/saddle installed on it too. When it comes home, I have new tuners (Grover 18:1 ratio) to install as well, and the case it came with to do some repair work to.