Design principles

The most important function of the guitar top (and back!) is to translate the string vibrations through an efficient bridge into musical sound. Traditional guitar construction uses a closed guitar box as a structure opposing the constant ~75 kg (or ~165 lbs) string tension. The top is then under constant compression, and the back is under tension, which prohibits free vibrations. It is not optimal. I envisioned a super light, very strong carbon fiber beam that goes throughout the length of the box. I consulted on my first design with Dr. Wojciech Grendysa from the Warsaw University of Technology, Department of Airplanes and Helicopters, and he kindly said: "Your design is not optimal." Which meant: "This is a bad design" 🙂.

He was kind and very patient, helping me design a much stiffer and lighter structure. Wojtek helped me a few more times when my understanding of physics or composite design was suffering. The carbon fiber beam in my guitars has the sole function of counteracting 100% of the string tension. It works similarly to the wooden center block in a Gibson ES-335. However, it weighs only slightly over 100 g (3.7 oz) and does not touch the top or back plates, leaving them free to vibrate.

When a string starts to vibrate after the guitarist strikes it with a plectrum or finger, the vibrations are transferred to the bridge and then from the bridge to the top. The wave, similar to that on the water in a pool, travels from the bridge toward the sides of the guitar. When the wave hits the side, its behavior depends on the impedance mismatch between the spruce top, as a wave-transferring medium, and the sides.

When the impedances of the top and sides are not very different, a lot of energy is compliantly drawn from the top by the sides. Many argue that this transfers energy to the back, but in reality, this is not a very efficient energy transfer. The vast majority of top and back coupling occurs through air pressure changes inside the box.

Designing a neck that does not vibrate and absorb energy from the strings is a challenge. As a glider pilot, I drew upon the brilliant design of the Diana 2 glider wing for my neck design. Bogumił Bereś, the structural designer of the Diana 2, omitted the heavy spar traditionally used in glider construction. Instead, he developed a multi-web-box design similar to corrugated cardboard. The result is the lightest glider in the 15 m class (182 kg compared to an industry average of 240 kg). While the wings maintain the same rigidity and strength as competing designs, they are 50% lighter.

In the photo—taken after I landed after a high-altitude flight—you can see the frost remaining where the internal structure of the wing retained the low temperature (also in the photo is my friend Sebastian Kawa, a sixteen-time world gliding champion, with whom we have done some great gliding projects).

I carve the top and back plates to their final dimensions only after the blanks are pre-bent. I follow the methodology described by viola maker Helen Michetschläger:

https://helenviolinmaker.com/wp-content/uploads/2017/04/Dartington-talk-transcript-with-pics.pdf

The advantage of this method lies in wood fiber alignment: bending allows the fibers to follow the arch contour, meaning fewer fibers are severed during final carving. Continuous fibers following the plate profile yield a stronger, lighter structure. This allows thinning specific regions down to 1.5 mm (under 1/16 inch).

The materials used in my guitars differ from standard luthiery choices.

Traditional archtop guitars were designed around materials and technologies available at the time. Lloyd Loar developed the Gibson L-5 — the archetype of the acoustic archtop — a century ago. While acoustic science and material engineering have advanced significantly since then, wood remains susceptible to long-term structural deformation (creep). Structural components can be redesigned using modern composite materials to eliminate creep while reducing weight.

Utility products in other fields have evolved similarly; wooden skis, leather ski boots, and wooden tennis rackets have been replaced by engineered composites. Load-carrying structures in my instruments are built from aviation-grade carbon fiber composite to ensure long-term dimensional stability.

The standard magnetic guitar pickup — invented nearly a century ago and 'perfected' almost 70 years ago — could likewise benefit from rethinking. The pickup coil is inherently balanced. Converting this to an unbalanced signal inside the guitar cavity, combined with high-inductance coils, increases susceptibility to mains hum and electromagnetic interference. High coil impedance paired with cable capacitance also restricts high-frequency response, creating a traditional vintage magnetic tone that does not represent the acoustic soundboard output. My goal was to design a pickup that complements rather than replaces the natural acoustic voice when using phosphor bronze strings (e.g., .012–.053 gauge)—a balanced, low-impedance design immune to interference that allows long cable runs without signal degradation, operating similarly to professional microphones.