The best acoustic guitar ever!

The story of my Marcos Labraga AC1 steel-strings double-top acoustic guitar.

Marcos Labraga AC1 – OM acoustic guitar.

Guitars are beautiful musical instruments! Based on this statement — which I hope you agree — let me tell you the story of my Marcos Labraga AC1 double-top acoustic guitar.

This guitar, which is an impressive combination of carefully selected materials and an exquisite luthier work, was designed during 2017 and built in 2018. It is called AC1, for being the first acoustic guitar (with steel strings) manufactured by luthier Marcos Labraga, a renowned Uruguayan classical concert guitars luthier.

Let’s know a little more about this guitar, its materials, its construction process, and of course, the luthier.

The design

The moment we started thinking about this guitar, the first question we asked ourselves was what will be its shape. As you may know, there is a wide range of sizes and shapes for an acoustic guitar, from the smaller ones (Parlor or OO) to the larger ones (Auditorium, Dreadnought or Jumbo).

Different acoustic guitar shapes and sizes.

Large guitars tend to have a deeper, lower sound, with more body and volume, while small guitars have a more mellow and intimate sound, emphasizing intelligibility. We decided to go towards an intimate but balanced sound, and that is why we selected an OM shape (Orchestra Model). On top of that, my guitars have all been Jumbo, Auditorium or Dreadnought shapes, so I also want to expand in sound range and have an instrument somehow different from the rest.

Here is a beautiful example of a guitar shaped like an Orchestra Model (Collings OM3).

Collings OM3 acoustic guitar.

The materials

We took a long time to carefully select the materials for this guitar, with several comings and goings. Finally, each chosen material has its reason for being, and its particular history.

Top wood

The top (or soundboard) is the active sound element in the body of the guitar. Although it is not the only element that influences the sound personality of the instrument, it has a high impact on the timbre and the color of the resulting sound. The best guitars usually have spruce or cedar tops, in their different variations.

Different tonewoods (source).

The first question we had to answer was: spruce or cedar? While cedar is the tonewood preferred by classical guitarists (using concert guitars with nylon strings) for its warm sound, the spruce is the most used tonewood in steel-strings acoustic guitars.

Spruce offers a brighter and sparklier sound. So we selected spruce, in particular, Engelmann Spruce. Engelmann is a good choice for players who want a more complex sound when playing softly, as it has stronger overtones and weaker fundamentals than Sitka spruce, for example. Engelmann can suffer when playing really hard, but it gives you an intimate and delicate sound with soft finger-style playing.

Selected Engelmann Spruce top wood.

Double top

Double-top guitars, also known as composite-top guitars, have two components to the soundboard, two independent soundboards glued together under pressure. Nowadays all double tops are actually three layers, the inner top, the outer top, and a middle core which at this time is usually composed Nomex (a flame-resistant meta-aramid material developed in the early 1960s, similar to Kevlar).

This construction method was introduced in 1989 by Matthias Dammann, a German guitar constructor and musician. Using this “sandwich” technique, he realized that he could increase his ability to control the acoustic characteristics, movement and character of the soundboard.

This double-top gives the guitar a very powerful sound and very responsive action, with rich beautiful sound, a broad color palette, an unusually large dynamic range, a superb sustain, even a good balance across the strings, and an exceptional playability.

A piece of Nomex, used as core for the double top.

Top bracing

Top bracing is essential to reinforce and support the soundboard, and to distribute the energy and vibrations coming from the strings. This process increases the rigidity of the top in some particular areas, favoring vibration at different frequency ranges, and giving the soundboard a full response to every tone generated by the strings. The same Engelmann spruce was used for the top bracing, except from the internal bridge reinforcement, made from jacaranda.

Top bracing woods (Engelmann Spruce).

Back and sides wood

The choice of the back and sides wood was one of the most difficult decisions in this guitar. The options were: jacaranda (India), cocobolo (Mexico), maple (Canada), and palo escrito (Mexico).

We know that back and sides wood does not affect the sound production of the guitar as much as the top wood does. However, a good pairing of the top wood with the back and sides wood is always sought. Having chosen Engelmann spruce for the top, we look for back and sides wood that accompanies the instrument’s intimate behavior in terms of the sound we want, without reaching a structure that is too soft. We also take advantage of this freedom to let the aesthetic aspects influence.

The final decision was a beautiful set of Mexican palo escrito, from Paracho de Verduzco, a small city located in Michoacán, in the south of Mexico.

Selected Palo Escrito back and side woods.

Back bracing

Back bracing is important to have a steady structure in the back of the guitar. The wood used for this bracing is not that relevant, except for basic rigidity and solidity characteristics, but every single touch in quality improves the overall result in the guitar.

It is usual to choose a wood that aesthetically accompanies the type of wood used for the back. In this case, a French cedar was chosen. These cedar boards were part of an old piece of furniture that was discarded after the demolition of a house of 1900, in Atlántida, Uruguay. Please appreciate the beautiful chocolate color.

Back bracing wood, French cedar.

Neck wood

For the neck we use Spanish cedar. This wood is traditionally used in the best Spanish concert guitars, since its beginnings. It’s like a touch of traditionalism in our AC1. In fact, Martin used this wood in the late 1800s and early 1900s. Then the mahogany become easier to find (and cheaper), and supplanted the Spanish cedar.

Neck wood, Spanish cedar.


The simplest decision of the whole guitar… Ebony, ebony, and ebony! We handle other options, such as Madagascar or Indian rosewood, but without a doubt the best option, both in wood hardness and look, is ebony.

Ebony piece for fretboard.

Truss Rod

We have a Hot Rod adjustable truss rod. It has a smooth 2-way action with superior strength for stubborn necks, that corrects up-bow and back-bow, giving complete control over the neck. In our case is a 14–1/4" overall length truss rod, specially made for acoustic guitars with 14th fret at the body.

Hot Rod adjustable truss rod.


For the bridge we use a beautiful piece of Indian jacaranda, with exquisite shades in reds and violets. A piece that will undoubtedly form an exquisite combination with the spruce top.

Bridge wood, Indian jacaranda.

Bridge Pins

Bridge pins could always be changed, but in this first time, we have some Waverly ivoroid pins inlaid with black dots, matching the Waverly ivoroid tuning machine's heads.

Bridge pins: Waverly ivoroid pins.

Saddle and nut

The most commonly used materials for saddle and nut are bone and ivory. Very solid and stable materials are required for saddle and nut, due to its efficiency when transferring string vibration to the body of the guitar.

In order to reinforce the search for an intimate and delicate sound, with controlled attack, we rather use a slightly softer material, ebony. However, since these parts are removable, this decision may change in the future.

Ebony saddle and nut in the finished guitar.

Peghead Veneer

The peghead overlay veneer is the the finishing touch of quality in the headstock. We selected a very beautiful piece of cocobolo, with ebony/white bindings.

Cocobolo peghead veneer wood, with ebony and white bindings.

Backhead Veneer

Backhead is also having an overlay veneer, an aesthetic complement that provides a quality finish to the guitar, and also enhances the back of the tuning machines. The material will be a beautiful piece created with the same set of palo escrito that was used for the back, giving a sense of design and coherence to the back of the guitar.

Selected Palo Escrito backhead veneer wood.


The rosette is made with fine wooden plates, some in their natural color and others dyed in different colors. Our rosette has two main components. The first, a spike made of light and dark woods, which is a trademark of Marcos Labraga, and can be seen in many of his guitars. The second, is a composition made with three woods (yellow / red / black), alluding to the German flag (since the soundboard is made from German wood, we wanted to crown the rosette with this detail).

Rosette woods and partial design.


We're going to use Stewart-MacDonald Medium/Medium frets. Medium widths are the most popular (used extensively by Martin, Fender and Gibson). Medium/Medium frets have this measures: 0.84" (2.13mm) width and 0.39" (0.99mm) crown.

Stewart-MacDonald Medium/Medium frets.


We want top quality tuning machines, that is a must! With that in mind, the decision of which tuning machines will we use ended up with two candidates:

  • Schaller Da Vinci: The Da Vinci is a state-of-the-art tuning machine featuring flawless construction, ultra smooth action and unparalleled tuning stability.
  • Waverly Tuners: with acclaimed design, precise 16:1 gear ratio, long-life stainless steel/bronze construction, and smooth, reliable operation, this are the favorite of renowned guitar makers and musicians for their finest instruments.
Tuning machines options: Schaller Da Vinci (left) and Waverly (right).

Both are very beautiful and precise machinery… I think the final decision will be made after having decided the shape and materials for the headstock.

Updated: Finally, and after several twists and turns, Waverly tuning machines were chosen :) The headstock is small and delicate, so the Waverly tuners fit better this design.

French Polish

Most commonly used to finish luthier-made classical and flamenco guitars, French polish is surrounded by more myths and opinions than virtually any other aspect of guitar making. French polish has been a common furniture finish since before the Victorian era and was probably first used on instruments as a faster-drying alternative to the very slow-drying varnishes used on violins. French polish shines with a delicious, organic, old-world elegance, and bonds perfectly to wood. Because it is extremely thin, it allows for the best possible tone, and it can be easily repaired and reconditioned at any time (source: Hill Guitar Company).

Luthier Marcos Labraga is an expert and passionate about this technique, giving the AC1 a fine touch of quality a traditionalism.

French polish when being applied to the top.

The construction process

The idea is not to describe the entire construction process of this guitar — since it involved several months of work, with ups and downs — but to leave a collection of pictures that show this instrument in its different building stages.

The Luthier

The Uruguayan guitar constructor Marcos Labraga, was born into a family with a very strong musical tradition. This led him to choose the guitar as his main instrument from a very young age, and thus received excellent academic training from teachers like Cristina Zárate and César Amaro. He later developed an active agenda as a concert guitarist, but grew increasingly interested in the art of guitar making. Two years after he made his first guitar, he opened his luthier workshop and in 2011 decided to dedicate exclusively to building classical concert guitars.

Luthier Marcos Labraga in his atelier.

Marcos Labraga's guitars are renowned among guitarists for their perfect details and exceptional craftsmanship, which are to be expected from a luthier who has also mastered the art of playing and can build his guitars with a critical musician ear.

His line of work focuses on double top guitars and traditional building systems, using the highest quality materials . His instruments have found acceptance in both Latin America and Europe markets, and are being played by guitarists like Mario Yaniquini (Argentina), Daniel Morgade (Uruguay), Ricardo Villanueva (Peru) and Manuel Espinás (Mexico).

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