The JMC Soundboard - Every detail counts

21 June, 2017

The JMC Soundboard - Every detail counts

The JMC Soundboard has been developed with a lot of attention. To underline the emotional content of the musical message delivered by the membrane made of 350 years old resonance spruce, every detail of the construction of this true musical instrument counts. From the condensers to the suspension, and even the varnishing; everything is built with the greatest care and by selecting only the best components.

First of all, we opted for a membrane made out of resonance spruce, known for centuries for its excellent response to vibrations and used on the best string instruments around the world. This wood can only be found in a few places and we selected the wood from the Risoud Forest, close to our factory in the Valley de Joux in the Swiss Jura Mountains. We select only one absolutely perfect tree among 10,000 in terms of location, environment and structure. One without knots, without resin spots, one that has grown preferably at 1'200 m altitude, slightly in a valley, one that has received enough sun, but well protected from the wind by the neighbouring trees. And above all, the tree has grown perfectly straight.

Gathering the tree also needs special attention, as it takes place at the end of the autumn by a descending moon. Then the tree can be cut in quarters or can be prepared for plywood. After waiting for many years, stored and stabilized in a humidity controlled environment, we can start the building of our instruments.

The first step is to select the finest slices of resonance spruce to create the inner and outer part of the membrane. The luthier makes sure that he selects a softer wood to be placed in the center which will underline the bases. He will choose a harder and more tonique wood for the outer parts of the membrane in order to underline the shining of the high tones. To stabilize the two parts of the membrane, he installs Nomex. This honeycomb made out of Kevlar is well known for its excellent resistance and lightness and had been used in the hulls of yachts like Alinghi or in the wings of the Solar Impulse airplane. In this way, the technical performance of the membrane is extremely high, while it keeps the poetic and musical performance of the resonance spruce.

The choice of actuators has been the subject of years of research and study. For now, only one type has met our requirements because only this one can make the membrane vibrate beautifully. We always speak of a real musical instrument because the membrane is tuned and is completely disconnected from its cover or the wall by a subtle suspension system. The elastic threads used are the same as those used in aerospace. In order to orient the frequencies, a three-way filter has been developed. Each electronic component is the best on the market. The coils, for example, are wounded by hand. The condensers were tested comparatively before we made our final decision.

Varnishing is an important phase, because the varnish must not alter the frequency equilibrium of the membrane. We therefore apply the same varnish as used on our guitars, in thin layers and not penetrating in order to preserve at best the harmonic properties of the spruce.

The result is a real musical instrument. On the one hand, the membrane is curved and mastered, tuned like the top of a guitar or the sounding board of a piano. On the other hand, this membrane is completely suspended and disconnected so that all vibrations are oriented into the membrane and that there will be no loss of vibrations. And above all, the emotional content associated with this living material that has spent more than 350 years of life and vibrations in the forest is incomparable. It is this content that is charged emotionally. The music played gives us a unique and unforgettable feeling and musical experience.