Martin OM-18 Authentic 1933

The first Martin OM made in modern times with truly authentic pre-war specs and construction techniques, the OM-18 Authentic 1933 seems to have stepped out of a time machine.

Specs include: hide glue construction; all solid woods including mahogany back, sides, neck; Adirondack spruce top with faded amberburst shading; ebony neck rod, fingerboard, 1933 style belly bridge, bridge pins; nut and glued in long saddle of bone*; 2-3/8″ string spacing; hand-carved replica V neck; Authentic style scalloped bracing with period-correct 5/16″ X brace and 1/4″ tone bars; many historically “authentic” details

* Bone replaced fossilized ivory in 2014.

Martin OM-18 Authentic 1933This new OM-18A 1933 is the first OM made with Martin’s Authentic Series specs and hide glue. And boy, is it a doozy! I played the prototype at the factory in January, when it was about as new as new can be. The Adirondack spruce top was extremely stiff, yet the voice already exhibited great depth, particularly in the mid-range. For all its light construction, it had a big voice, with that famous OM projection so that the lightest playing produced enormous amounts of tone. With mahogany for the back and sides, the OM-18 Authentic 1933 sounded clear and full at the same time. And it can be played at full throttle without wigging out, it just gets louder and more powerful.

I played an example of the production run some months later, over at Maury’s Music, in Coaldale, Pennsylvania. In fact, I was the first person to play it right out of the box it came in. It is like taking a time machine back to 1933 and getting your hands on a brand new OM-18, made the year C.F. Martin and Co. celebrated their 100th anniversary and were busy setting the gold standard that all acoustic guitars have been compared to ever since.

Even though it was just as new as the prototype, it was noticeably more awake and lively. Where the prototype felt light, but not as light as I expected, or as light as I remembered the many vintage OM-18s I have played, this new one felt every bit as light as a 30s OM-18. Where the prototype felt stiff and the strings felt tight and difficult to bend without notable effort, this new one was effortless to play and the slightest change in string pressure or bend sent resonating quivers through the tonal spectrum. I thought to myself, “Now this really is the OM-18 of old brought back to life.” It has everything that made the original Orchestra Model design the stuff of legend.

A Legacy of Firsts

The first modern acoustic guitars appeared in the 1930 Martin catalog, named the Orchestra Model to appeal to dance orchestras. They were the very first 14-fret guitars made by Martin, and the first Martins designed expressly for steel strings.

The OM models were renamed the 000 at the start of 1934, to fit into Martin’s traditional naming convention. A few months later they were converted to thicker bracing and the short string scale used on the smaller 0 and 00 sizes, which changed their dynamics and sound ever after.

Martin eventually brought back the OM design, beginning in 1969 but not in earnest until the 1990s, with traditional OM specs that included a long-scale, 1-3/4″ neck and a small, maple bridge plate. And they used narrow 1/4″ scalloped braces in an effort to create dynamics and resonance similar to the old OMs, while still employing modern wood thicknesses and construction techniques.

Whether people at the factory forgot about it, or never noticed, the original OMs actually had a center X brace that was 5/16″, surrounded by 1/4″ tone bars. The OM-18A 1933 is first Martin OM since the early 30s to have this specific feature.

The two previous mahogany OM models made in the modern era were the OM-18V 1933 from the Vintage Series, and the OM-18GE 1930 of the Golden Era Series. Both had 1/4″ scalloped braces. But while the GE had a lighter build overall and more wood removed from the braces, the OM-18V had the same build as the Standard Series Martins, with the exception of a V neck and wider string space.

The OM-18V had great power and resonance; standing up to the most ferocious attack. But it lacked the open, ethereal undertone of a vintage guitar, and was not nearly as responsive when played with a light touch. The OM-18GE was extremely responsive to nuanced playing, and was quite open-sounding, but it had thinner fundamentals compared to other OMs, particularly in the trebles, and the top was easily over-driven when put under serious attack.

The First Authentic OM

This new OM-18A from the Authentic Series may have the lightest build of all, with thinner woods and thinner finish than any Martin OM made since World War II. But its 5/16″ X-brace bars are thicker than either of those other OM-18s, while keeping with 1/4″ bracing throughout the rest of the top. To my ear, that stiffer center gives it a more focused punch straight out of the sound hole, reminiscent of a traditional 14-fret 000. But with the thinner 1/4″ bracing spread out around the top, it also has a more-open resonance that expands in all directions, just like an OM should. The sustain of the fundamental notes is stunning, again more like a 000 than many modern OMs, which tend to have fundamentals that fade into the resonant undertone. But there is still so much presence to the expansive glow of the sympathetics under and around the fundamental notes that the voice has OM written all over it.

The OM-18A 1933 just seems to come with the Goldilocks’ “just right” combination of responsive dynamics, fat fundamentals with righteous sustain and a focused punch out of the sound hole, surrounded by that expansive OM openness, and genuinely impressive projection, power and attack ceiling.

While the bass was restrained, and the strings seemed notably tight, due to the newness of the stiff Adirondack top, the prototype had all the earmarks of developing into a beautiful monster of a mahogany OM. The ones I have played since showed the production version has arrived tweaked to mahogany OM perfection. And I must confess to feeling a slight thrill at the thought that the guitar sounds worse right now than it ever will again.

With the period-correct 2-3/8″ string spacing and a 1-3/4″ neck that has a noticeable V profile, there is ample space for fingerstylists, while some players may find it a bit wide for comfort when thumb-fretting up the neck. However, I am extremely picky about necks, due to old injuries, and I found no issues with this neck. After sampling many examples of the inventory at Maury’s Music, the OM-18 Authentic 1933 was my choice to while away an hour of spare time. I never experienced anything along the line of discomfort I often feel when playing V necks.

And this particular model comes with a shaded top. Martin used that cosmetic feature during the Depression era on a higher percentage of guitars built in Style 18 than other styles. And this version is purposely faded out some, so it closely resembles the 80-year-old OM-18 shade tops, which you may be lucky to find on sale a bit under $30,000.

Is owning the new OM-18 Authentic the same as having a 1933 OM-18? Nope. No one can take a new guitar and infuse 80 years of “playing in.” But I have to say, this is about as close as you will get to buying a brand new 1933 OM-18 in 1933, and certainly for the price!

List price: $6,499

But don’t let that fool you, I suggest you give your favorite dealer a call to find out what a good deal these wonderful OMs really are, in terms of street money, and just how long it will take for Martin’s Custom Shop to build yours.

And that is one man’s word on…

The Martin OM-18 Authentic 1933

Read more about C.F. Martin & Co. HERE

Other reading:

OM-28 1931 Review

The OM Story

Read our primer about Martin Model Designations and Naming Conventions HERE

Here is a video shot at the Martin factory the day the model was released to the public in January, 2013.

It was shot with a camcorder. In the future, we hope to offer video of this model and others from the Authentic Series. Starting in 2014, most of our on-site videos offer the same kind of hi-def audio we use for our in-house videos.

Do you own a Martin OM-18 Authentic 1933?

Have you played one?

We’d love to read your opinion and thoughts!

17 thoughts on “Martin OM-18 Authentic 1933

  1. I received one as a gift a few days ago and so far I simply love the way it feels. Either finger picked or flat picked the vibrating feels good against my chest. I love the sound; to me it sounds like a warm and rich.

  2. Your reviews are wonderful and I want to thank you. I have to consider myself ma OM fanatic. I have owned an OM-18(1932), and two OM-28’s(1932 and 1931). I had to sell all of them. I now play a TJ Thompson -Schoenberg soloist from 1990, or there about It is a wonderful guitar. One of my ex-OM-28s had the finest tone I have ever experienced except for an old beat up Washburn that Jon Lundberg let me mess with in the late ’60s. As far as this OM-18A is concerned I am saving every last penny for one. Again, I thank you for a great web site.

  3. I’ve had mine for about a week, (the new VTS version). There are some things I like about it, but by and large I can’t say that I’m loving it. It does sound kind of like some of the vintage small bodied mahogany Martins I have played- dry (just this side of brittle actually), airy, amazing clarity (especially in the trebles), and headroom to spare. But it also sounds kind of cold, with no complexity or warmth at all. Not much sustain, and nothing in the tone that I would describe as sounding rich. It fact I’d describe it as being tonally on the stingy side. It is impressive when I really lay into it with a pick, playing leads. It’s playing finger styIe that I get frustrated, particularly if I’m trying to get a lyrical sound. I do think the neck shape is very nice, especially as I go up the fretboard. It is a very light and comfortable guitar to play, so I really want to like it. I’m going to give it a few months, but right now it’s a candidate to be the first Martin I’ve moved along in quite awhile. I’ve read stellar reports from other owners, so perhaps my ear and taste in this instance run wildly outside the norm, I don’t know.
    I do want to say thank you for what you do here. I think you provide a great service that is intelligent, informative, and entertaining.

    1. To me, it sounds like you are describing the typical Adirondack on mahogany voice: dry, clear, pure, ringing, but sparse when it comes to things like warmth and complexity.

      The old 000-18GE and 000-18 Authentic could be described the same way, a very clean clear, fundamental-heavy sound. Warmth and presence will come out of the bass, but not like it does on the dreadnought 18s.

      It is a sound some players covet and prefer over all others. But it is one reason I like Sitka spruce in mahogany, I prefer a bit more going on in the undertone.

      But I will say, the guitar will sound more complex over time, but it will never have the kind of complexity a 28 has and it will never have the kind of warmth that Sitka, Engelmann, or Alpine spruce add to the mahogany sound.

      1. I actually do like the sound of the 000-18GE quite a lot. I own a couple of different OM-18 models (one adi, one sitka). I guess I expected the Authentic to blow those away, and it doesn’t seem to be in the same league, at least not with the one with the adi top. I will give it some time. I don’t want it to sound like a 28, but I am hoping for a little mere complexity and warmth. Thanks again.

    2. Stephen found: “no complexity or warmth at all. Not much sustain, and nothing in the tone that I would describe as sounding rich. It fact I’d describe it as being tonally on the stingy side. It is impressive when I really lay into it with a pick, playing leads. It’s playing finger style that I get frustrated, particularly if I’m trying to get a lyrical sound”

      I too purchased an OM-18 A VTS about a week – six (6) days ago, and was not overwhelmed – until a bit later.

      I spent about three (3) hours auditioning the brand new guitar that I had ordered six months prior, in the shop prior to purchase, and probably violated many of the guitar purchasing principles. It did not sound great to me initially. I did take the word of others, and I did consider the name on the headstock. It was a source of great anxiety, for while I feel the price is reasonable, even very good, it is substantially more than other Martins. On paper or intellectually, everything seemed right. I like an Adirondack over mahogany OM, the neck was not a problem even playing with thumb over the bass note on the 8th fret, and playability overall was excellent. I could tell the build quality was first rate and the torrefied top braces looked like a work of art (viewed with a lighted mirror). While light, the guitar felt very solidly built. But the tone didn’t wow me as expected from one of the quintessential pre-war instruments.

      On the recommendation of Ted at LA Guitar Sales, and combined with the fact that on paper it seemed ideal, I went ahead with the purchase.

      It should be noted I play finger style only. No finger or thumb pick, or flat pick. So the items you mention about lyrical tone, sustain and warmth are of primary importance to me.

      The next day I was working on a pieces with some more intricate barré chords and decided there is no reason to use the full medium MSP7200 string set supplied, so I changed to the John Pearse New Medium strings I have been using.

      I should also mention that this guitar was absolutely brand new. I arrived the day prior from Martin. During the first few hours, it seemed to me the trebles began to open up some, but the bass not so much. I probably spent another three hours at home trying to get the guitar to open up in one day without any real success.
      However after the first few days, there is a noticeable improvement. I started to appreciate the neck profile and began to discover that I could play more challenging passages error free and more easily.

      Now I am finding a significant improvement in tone. There’s a reverberation and richness to the notes that I didn’t notice before and I’m beginning to get a great deal more satisfaction from playing music. It occurred to me that actually the guitar has everything I was seeking, first rate build quality, custom shop attention to detail, great playability and excellent tone.
      It seemed to me two days ago, that I needed to “tell” the guitar what I wanted, as in repeatedly playing a particular note or series of notes, and as they were emphasized and repeated, the tone seemed to improve.

      Now only 6 days after new in the box, the guitar is responding to light pressure with rich tone and great sustain, plus that endearing reverberation.

      This must be what Chris Martin III meant when he said the new guitar is the worst it will ever sound.

      I also feel the VTS added a mellowness to the tone right from the start. The example I saw given, was that one can liken it to finding an old guitar in the closet that hadn’t been played. The basics are present, but it needs to be put back into play.

      One final comment. The torrefied braces are very light in color. No darkening at all, which I like. They stopped the process at the right point.

  4. Most OM’s usually come w/ light gauge strings. Why is the OM-18A is outfitted w/ Mediums? Every time I string my OM’s w/ a heavier gauged string, the guitar seems to lose it’s sparkle/clarity & becomes somewhat muddier sounding. Your OM-18A Video doesn’t display any of the medium string gauge muddiness I’m referring to. If anything, it’s extremely crisp sounding…

    1. When I played that prototype of the OM-18 Authentic 1933, I thought for sure they had to have put medium gauge strings on it, because they were just SO darn tight and required a lot of effort to bend.

      I have pondered the why behind that choice ever since. My guess is the official line may have been “they used heavier strings in those days.” In fact, people were using piano strings and wire from screened doors before the guitar companies caught up to the public’s interest in steel strings. But by the 20s you could buy steel strings easily enough. But they were indeed heavier than what we use today.

      Really? I think they were were afraid the 5/16″ X-brace was going to curtail the resonance that OM players were used to hearing in a Martin OM made with all-1/4″ bracing. So, they put mediums on to help that new, stiff Adirondack spruce top move as much and as soon as possible.

      The fact the guitar has an ebony nut doesn’t help when it comes to as much resonance as possible right out of box.

      But anyone who has put light gauge strings on an OM-18 A has learned it has plenty of resonance without the need for mediums.

  5. What are your thoughts regarding the ebony nut? How does it compare with bone in terms of tone and durability?

    1. Hi Jose, and welcome to One Man’s Guitar.

      As with all wood, the ebony nut takes some time to break in. But they sound fine. The OM-18GE had one too.

      There are many vintage guitars that have their original ebony or rosewood nut, so I do not think it is a concern for the long term

      However, I still think a bone nut will give a clearer, brighter ring and if I had one of these guitars, I would pay someone who knows what they are doing to replace the nut, but keep the original in case I liked it better.

    1. Jeffery,

      Thanks for asking a great question.

      The simple answer is, that is what you have to do if you want a guitar made as exactly as possible to the original Martin OMs of the 1930s.

      The full answer is more like this: The original OMs made between 1929 and 1933 all had an X-brace of 5/16″, while all the surrounding tone bar braces were 1/4″.

      The very first guitar made with the orchestra model specs, the 1929 special order built for Perry Bechtel was lost to history, probably in a fire in Atlanta. But scholarship suggests that it too had this configuration.

      No one knows for sure why Martin used a 1/4″ X-brace when they first revived the OM in 1969 for a limited run, and then when they brought the design back into production in later years.

      It is possible that it’s simply an oversight. Maybe someone looked at an old drawing and saw 1/4″ written down. Perhaps someone stuck some calipers inside an old OM and measured a single brace and assumed they would use the same thickness for all the braces. Who knows?

      Whatever the case, I consider it a very fortunate accident that the modern OMs were all made with 1/4″ bracing throughout. They have thicker wood and a thicker finish compared to the Martins made in the 1930s. The extra-light bracing allowed for a resonance that better exemplified the old featherweight Martins, and that made the new OMs stand apart from the tighter, punchier 000s, which have the same body size.

      This new OM-18 Authentic 1933 has thinner woods and a thinner finish, more like the old timers. While I do think it is a bit more gathered and punchy out of the sound hole compared to something like the OM-18 Golden Era, the Authentic has much plumper trebles than the GE and more power over all, while still having that ethereal and expansive resonant glow one looks for in a classic OM.

      I remain a big proponent of scalloped 1/4″ bracing for modern Martin OMs, and especially short-scale 000s which mostly retain the thicker 5/16″ bracing overall. But if you want an exacting replica of a 1930s OM, the 5/16″ X-brace is an integral part of that particular time machine.

  6. In late 1972 or early 1973, I learned about the original Martin OMs in an article in Crawdaddy magazine. Pictured there was a 1932 or 1933 OM-28. The model was late enough to have the long pickguard, guitar tuners, belly bridge and the headstock logo. Thus started my 40 year fasination with Martin OMs. The OM-18V and the OM-28V models frustrated me because they didn’t accurately represent the original OMs in any of their various configurations, either early or late. I acquired an OM-18A at Gruhn’s in May. I couldn’t be more thoroughly satisfied; my OM frustrations are resolved; at last…a new Martin OM that really does replicate the sound and the appearance of the original ones, and it’s in the late configuration that is my personal favorite.

    1. Thank you for sharing such a great story, Craig!

      Your personal journey has similarities to those from other members of the OM cult.

      I remember standing in Chris Martin’s office in 2002 thanking him for bringing back the OMs, and impressing upon him the need for an OM-18 and then noting the skeptical look he had in response.

      I remember discussing with Martin designers the virtues of some of the exacting OM replicas being made by TJ Thompson and Jim Merrill, and their response being such luthiers made so few guitars they weren’t on the radar in terms of business competition.

      And I remember them getting closer and closer, through the Standard Series, the Vintage Series, the Marquis Series, and how the Authentic Series decided to go with a 000-18 instead of an OM.

      And now, finally, they have come out with something even a nitpicker can pick, and a vintage OM lover can love – especially at such a reasonable price.

    1. Jeffery,

      While I played a few OM-28Vs this weekend at Martinfest, I have not played the OM-18A 1933 for a couple of weeks now. But my memory of it says that the V is more noticeable across the center of the palm, so it is a bit pointier and the way the slope of the V comes down toward the fretboard made my palm spread out a bit more, so it feels wider, even though the fingerboard are actually the same width. And to that the slightly wider string spacing and I would say the 28V experience is a bit “smaller.”

We and our readers would very much like to hear what YOU think.

This site uses Akismet to reduce spam. Learn how your comment data is processed.