A Genuine Mahogany and Torrefied Sitka Spruce D-18 with Modern Acoustic Engineering

The D-18 Modern Deluxe Offers Awesome Upgrades to a Classic Martin

Specs include: All solid wood construction; Genuine South American mahogany back and sides; torrefied Sitka spruce top with scalloped, forward-shifted, torrefied Adirondack spruce bracing attached with natural protein glue; composite carbon fiber/torrefied Adirondack spruce bridge plate; Genuine South American mahogany neck with Vintage Deluxe profile, satin finish, two-way adjustable titanium support rod, hand-fitted dovetail neck joint and solid mahogany neck block; ebony fretboard with High Performance Taper, 1-3/4” width at nut, 2-1/8” at 12th fret, abalone vintage Style 18 position markers, EVO Gold frets, solid bone nut; ebony bridge with Liquidmetal® bridge pins, compensated solid bone saddle and 2-5/32” string spacing; Indian rosewood binding, end piece, heal cap; multi-stripe top trim; high gloss nitrocellulose lacquer body finish; high gloss Indian rosewood headstock faceplate with abalone script logo and golden Waverly open back tuners with butter bean knobs.

“It is just so vibrant and alive. The energy streaming through the wood of the D-18 Modern Deluxe is palpable each and every place it comes into contact with the player’s body – very much like a pre-war Martin. And the futuristic elements of torrefaction, neck rod, bridge plate, and bridge pins combine to convert as much of that energy into audible tone as possible, while creating a voice and personality that is unique among Martins.”

Mahogany Dreadnought Like No Other

Martin’s D-18 Modern Deluxe is a Dreadnought size acoustic guitar made in a special version of their venerable Style 18, unique to the Modern Deluxe Series, combining the latest advantages in modern acoustic engineering with impressive deluxe appointments. These include a soundboard of torrefied spruce, a titanium neck rod, wooden bindings, EVO copper frets, Liquidmetal bridge pins, and a carbon fiber bridge plate. It has new looks and a new Martin sound that are exclusive to the Modern Deluxe Series.

As the first Modern Deluxe model made with mahogany back and sides, the D-18 MD shines like a patch of sunshine among the forest of rosewood models. It has an honest, joyful voice that is straightforward – the fundamental notes standing out with clarity from a woody body resonance, and igniting a steely vibrancy glinting off the high end of strums like white caps on the waves of a warm, tropical sea. There is an openness, clarity, and marvelous sustain that should be at once familiar to an ear tuned to Martin mahogany guitars, and yet fresh and impressive on many levels, because there seems to be more of such things than usual.

Along with the other models in the new Modern Deluxe Series, the D-18 MD fits into the Martin product line at a price point beneath the lofty Authentic Series, filling the void left by the various vintage-esque mahogany dreadnoughts from the now-defunct Golden Era/Marquis Series and Vintage Series. But the main competition for the D-18 MD is not the D-18 Authentic 1939, but rather comes from the tier below it, in the form of the basic good ol’ D-18 in Martin’s Standard Series, which is closer in terms of price and specs.

The Standard D-18 is an exceptionally good guitar. It has particularly popular since it was redesigned in 2006 to have the bracing and the looks of the retired D-18V in combination with Martin’s modern High Performance neck. The upscale additions in this new D-18 Modern Deluxe are carefully thought out and united with ultra-modern, innovative technology to create a truly modern and seriously deluxe version of the Martin D-18, from its headstock to its end block.

Deluxe Details

Unlike Standard Series Martins with their decal logo of gold foil, the Modern Deluxe logo is inlaid with glimmering abalone shell. And the script is a little more ornate in its curvature and serf accents then the C. F. Martin & Co. most people are familiar with. That is because it is based upon the logo used for but a short time, when Martin first started putting logos on the front of the headstock, circa 1931. This new version of a traditional Martin feature is a theme that is experienced throughout the D-18 Modern Deluxe.

At the back of the headstock are gold-colored Waverley tuners, considered superior in quality to most tuners on the market. Various people have wished Martin would use Waverlys more often. Now, they come standard on the Modern Deluxe models. But they are also the golden ones, formerly found on fancier Martins, typically made in Style 42 and 45.

But then, this is a snazzier D-18 MD and an obvious step up from the Standard Series version in its styling. The flashier aesthetic of the headstock appointments continues down the neck with abalone position markers inlaid along the jet black ebony fingerboard, rather than plain white mother-of-pearl, so they match the colorful logo. Even the side dots are made from iridescent shell, in this case paua from New Zealand. Paua reflects light marvelously well when the stage is darkened between songs, or turns a deep red or green, etc. And gold-colored EVO frets set off the Waverly tuners very nicely indeed.

EVO is a brand name derived from “evolutionary,” and the golden hue is actually the natural color of the copper alloy used to make the frets. It is nickel-free and is harder than the German silver used for most frets, so these Modern Deluxe frets should withstand many more hours of dedicated playing without wearing down.

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Historic Neck Shape

The neck is also quite different from the standard series instruments, both in terms of its interior support rod, and the shape of the neck itself. Where the Standard D-18 has the Modified Low Profile shape used for most Martins these days, the Modern Deluxe Series has Martin’s new Vintage Deluxe Profile shape, which is based on a very special neck from a very special vintage Martin, the 1930 OM-45 Deluxe now owned by the Martin Museum.

Those with a fear of big, bulky V necks can rest assured that this neck has much less depth and girth than most vintage Martins, and with less of a V to its profile, and it is considered to be remarkably comfortable as a result. But the real secret to its exceptional comfort is how the profile is “skewed,” as Martin is calling it these days.

The Vintage Deluxe profile is asymmetrical in its shaping. The slope of the bass side is different than the treble side, and the apex where the neck is deepest begins off-center and drifts. As the hand and wrist change their angle the farther they go up the ever-widening neck, the apex of the neck shifts right along with them.

This is a new concept in neck shaping at Martin. Or rather, it is a return to how they carved and sanded necks 80 years ago, before the art was lost to history, and only recently rediscovered. This skewed effect is quite subtle, yet matters greatly in terms of playing ease.

Read more about the Vintage Deluxe Profile and what makes it so special HERE.

The D-18 MD neck is not an exact copy of the old OM neck. In fact, the fretboard on the D-18 Modern Deluxe has Martin’s modern High Performance Taper, which starts at 1-3/4” width-at-nut but measures 2-1/8” at the 12^th fret (1/8” narrower than a 1-3/4” neck from the 1930s.) So, it has the same fretboard taper and 2-5/32” string spacing as the Standard D-18. The two necks are more similar than not in terms of overall size. And yet, the shaping of the mahogany makes a big difference.

Also, the shape of the heel is different from the original 1930 neck, so there is less mass to the mahogany as it transitions into the extended neck, leading to a more modern feel at the uppermost frets. Players who love fat vintage V necks may find the Vintage Deluxe profile surprisingly shallow, even though it is surprisingly close in shape and girth to the neck it is based on. And those who do not get on well with the Modern Low Oval may find the new neck very much to their liking, no matter how thick or not they prefer their necks.

Light and Strong

Another important difference with this neck is its titanium truss rod. It has the same engineering and design as Martin’s normal two-way adjustable steel truss rod, but it weighs less. It is so much lighter that it gives the entire guitar a different sense of balance between the body and neck, one that’s much more like a vintage Martin made with a metal T-bar, or even a wooden dowel for its neck support. And while all of the Modern Deluxe models have that same sense of vintage Martin balance, it is the D-18 MD that stands out in this regard, because its mahogany back and sides are so much lighter in weight than the Indian rosewood used for other Modern Deluxe instruments.

While the D-18 MD is reminiscent of a pre-war D-18 in terms of overall weight and balance, it feels even more like a vintage Martin in how the neck vibrates in the hand from even the most basic strumming – all the way down to the nut. I must assume the titanium alloy rod is responsible for this incredible increase in neck vibrations. And much of that energy, busily vibrating through the solid mahogany neck, is free to make its way to and through the traditional, hand-fitted dovetail neck joint to the solid tonewoods that make up the D-18 MD’s sound chamber.

The tonewoods used to create the sound chamber are genuine South American mahogany for the back and sides, and a Sitka spruce soundboard, just like on the Standard D-18. But this Sitka spruce has been torrefied via Martin’s Vintage Tone System, which uses intense heat to accelerate the aging process, resulting in brand new spruce that takes on physical and sonic properties similar to wood that has seasoned for several decades.

I have said repeatedly that, to my ear, VTS Sitka sounds a bit drier and has more of a midrange bark than untreated Sitka. In this regard, it can be said to sound bit more like Adirondack spruce. And it also makes a fledgling guitar sound more “opened up.” Individual notes and hefty strums don’t seem to skip off the surface of a brand new top, but effortlessly expand in depth and projection, much more like a guitar with some years of playing under the hood. And all these attributes are heard distinctly in the D-18 MD. And as the VTS removed the inherent moisture in the cells of the spruce, the top lost mass, making it lighter in weight without losing its strength.

Read more about Martin’s VTS treatment HERE.

VTS Sitka spruce has appeared on limited editions for some time. But the Modern Deluxe Series marks the first time it is being offered as a regular feature of an entire instrument series within the Martin catalog. But unlike those other Martins, the Modern Deluxe models also get VTS-treated bracing, which had been exclusive to the Authentic Series instruments. And the bracing is made from Adirondack spruce, rather than usual bracing of Sitka with Sitka. Adirondack is stiffer than other spruces, while having great resiliency at the same time, so it can be carved thinner. And that is exactly what Martin did when they used the Golden Era technique to scallop the braces supporting the D-18 MD’s soundboard.

GE bracing was developed for the old Golden Era Series instruments, meant to respond more like vintage Martins than the Standard Series and Vintage Series guitars. Likewise, the bracing is in the forward-shifted position, meaning it is about an inch farther away from the bridge plate, further freeing up the back half of the soundboard to respond better, leading to more overall resonance and an increase in bass response.

While the VTS spruce and GE bracing are meant to provide a more vintage-like tone, there are two other elements in the acoustic engineering of the D-18 MD that are decidedly ultra-modern – the carbon fiber bridge plate and the Liquidmetal bridge pins.

Effortless Tone Production

The bridge plate is a composite of two very thin plates of carbon fiber sandwiching a piece of VTS Adirondack spruce. The result is a bridge plate that is incredibly stable while also providing far less dampening compared to traditional bridge plates.

This is important because most of the tone-producing energy from the vibrating strings enter the instrument at the saddle, which vibrates the solid ebony bridge and the supporting bridge plate on the underside of the spruce. And those vibrations are then transferred to the soundboard and disseminated across it via the spruce bracing.

The carbon fiber provides unsurpassed stability and protects the thin spruce plate within it from years of string ends being pulled against it with nearly 200 pounds of force when tuned to concert pitch. And the spruce itself is lighter than other woods used for bridge plates, including maple. The torrefaction processes has crystalized the cellular interiors of the wood, so it allows maximum energy to pass from the strings to the VTS spruce top and bracing.

To a lesser extent, string energy is likewise injected into the bridge plate where the strings anchor inside the instrument, held in place by the bridge pins. And this process is enhanced by the use of Liquidmetal bridge pins, for similar reasons. They decrease energy dampening.

Liquidmetal is a patented product created with the amorphous molecular structure of a liquid. In other words, it is a kind of metallic glass, which is very good at conducting energy without absorbing much or any of it as it passes through. I may not have played a guitar that had only the Liquidmetal pins or only the carbon fiber bridge plate. So I cannot comment on which is doing the most to affect to the tone of the D-18 MD. For that matter, the neck rod and VTS spruce and bracing also must enter into any equation when it comes to why this guitar sounds like it does.

But I can say I have played multiple limited editions that had these pins and this bridge plate, and they all appear to have increased volume, clarity, fundamental sustain, and an impressive bell-like chime; and so too do the Modern Deluxe models. But the D-18 MD may just take the cake.

It is just so vibrant and alive. The energy streaming through the wood of the D-18 Modern Deluxe is palpable each and every place it comes into contact with the player’s body – very much like a pre-war Martin. And the futuristic elements of torrefaction, neck rod, bridge plate, and bridge pins combine to convert as much of that energy into audible tone as possible, while creating a voice and personality that is unique among Martins.

When I dig in and play it hard, there is a little more bark and rasp to the fundamentals from the wound strings that fire out of the sound hole. But it doesn’t get all that throaty, compared to the Standard D-18. Someone who really loves the roar of acoustic overdrive might prefer the Standard D-18 as a result. But many others will love how the D-18 DM snarls when provoked, and how hammer-ons and big bass notes maintain their definition when under attack, and also how they reach way down into the body, as if there is nothing solid there to impede them.

Neither does the D-18DM get thin and whispery when played very lightly. It retains the refined clarity of the unwound strings and the solid definition from each note below them. The identity of each string remains intact at all levels of attack and volume. Even by mahogany standards, it is a very clear, clean voice, without out a lot of darkness to the top voice or shadows in the cellar.

Now, it there not a huge difference from the mahogany voice of a D-18 or other mahogany guitars. But with the D-18 MD, it is a different recipe of tone production, leading to a unique version of the mahogany Martin sound. The sonic properties that are most notably different from the Standard D-18 are the treble chime, the fundamental sustain, and the effortless depth and openness of this instrument.

It has a very particular chime coming off the strings, and from the treble most of all. It is quite focused and bell-like, but very much in the metallic way as opposed to glass – like silver bells if not orchestral bells.

There are acoustic guitars with tonal properties that make me think of a piano, and those that make me think of a cello, and some that even make me think of an electric guitar. But the D-18 MD, bells and all, just keeps sounding like an acoustic guitar, and a very musical one at that.

Not that there isn’t a glassy quality to this mahogany voice; there is! At times it is like the voice has so much depth behind the top notes, and yet it is transparent. Listening closely to the voice can be like looking down through the glass roof of a spacious atrium in a modern office building on a summer day. And hammer-ons or glides up and down strings produce sound that leaps as deep into the voice as it leaps out into the room. They produce no tension or decrease the sound of the original note. They just produce varying tone. And the sonic illusion of 3D space inside the voice and projecting the top notes is extended by the impressive fundamental sustain.

By fundamental sustain, I refer to the actual initial note that is picked, plucked, or strummed, and how long it remains at or near its peak loudness. But I am also referring to how long it remains solid and sure at its initial pitch without veering or reverberating out of its lane, as it were.

It is not something all that noticeable. But when one has been around as many Martins as I have, it is immediately apparent how the notes stand out into a room and maintain that volume just a touch longer than normal, so that it is often impossible to tell where the fundamental note is taken over by a unison sympathetic from another string. There isn’t a lot of swelling and receding, but steady streams. The transfer of the dominant tone is effortless. It is also related to why sympathetic undertone or high overtones rarely if ever override the fundamental notes. It is an attribute that is simply different from Martins made without all the special engineering.

And the chiming quality off the top end isn’t particularly pronounced. It isn’t a dominant feature, so much as effortless – that is the word that kept coming to mind when I played the guitar, and when I listen to my hi-def recordings. It fits with the fatter mid-range notes and the rounder, deeper bottom end notes. They work very well together and create an overall sound that remains familiar yet new, with nothing overshadowing anything else.

There is no way to say what exactly is responsible for the specifics in the D-18 DM voice, or other Modern Deluxe models. But that open depth phenomenon is very much about the VTS torrefaction and the GE bracing.

I love my mahogany with Sitka spruce. I like how it spreads the bottom end warmth up into the other registers, and how it adds some colorful glow to that the fundamentally straightforward mahogany tone. Torrefied spruce takes away some of that warmth and adds some crisper definition and drier sympathetic undertone. That is why some people say it sounds a bit more like Adirondack spruce. It is less mellow in tone because it is punchier, just as it is more fundamental and less overtone-ish. But it is also creates a voice so much more open and “effortless” right out of the box.

My mind’s eye hears it this way: When I play a note, picking pattern, or chord, a typical new guitar puts out a “tone bubble” that is egg-shaped, with the widest two-thirds out in front of the guitar, and the other third reaching down into the body, and requiring a lot of energy to get in there with varying success.

With the VTS in play, that tone bubble reaches all the way down into the body with little or no tension. So tone exudes from the instrument in all directions, and the inner space of its tone bubble is much more expansive. It is not like the egg is shifting backwards. It is a much bigger bubble that reaches all the way down into the body of the guitar, while it also projects outward as far or beyond that of the non-VTS D-18.

The interior of that bubble is not as thick or woofy as the Standard D-18 voice. The space is more open, more airy, and the notes filling that inner space are more translucent, and yet they fill the inner space in a way that makes it so remarkable and delicious. It makes it sound like a very old guitar – at least in this particular aspect.

I will never say torrefied tops make new guitar sound just like a vintage instruments. They do not. And in the case of the Modern Deluxe models there are other aspects of their tone that is less traditional and more contemporary, which will make them highly competitive in the greater acoustic guitar market, particularly with younger players. But the fact the D-18 MD doesn’t sound quite like any D-18 before is also what will appeal to certain traditional Martin owners looking for something special or out of the ordinary for their next Martin.

I do like how there are things about the D-18 Modern Deluxe that makes me think of a vintage guitar when I am playing it, in how it feels in the hands, and the weight and balance when lifting it and moving it around, and in the effortless 3D depth of that mahogany tone bubble.

With the Vintage Deluxe Profile neck and wide open voice, the D-18 MD is fun to play, with a new sound that will inspire new music from its lucky owners. And thanks to the abalone inlay and golden hardware, as well as its boutique rosewood bindings and the natural top shading that comes with the VTS treatment, it has replaced the visual austerity of a typical mahogany Martin with styling that catches the eye while keeping the overall aesthetic balanced between the beautiful wood and its pretty appointments.

With such a successful mahogany dreadnought, I am looking very forward to the OM and 000, as the Modern Deluxe Series expands in the upcoming months and years.

And that is one man’s word on …