Thermo Treatment

Tonewood carefully selected by us goes through a strictly controlled process, resulting in Thermo Treated tonewood with various superior properties. The treatment affects to the cellular structure of wood – by changing it nearly identical to timber that has naturally aged for decades.

thermo2From the guitar maker’s point of view, the best and most apparent affect of Thermo Treatment is the increased stability of the wood. Simply, this means less adjusting for necks and more relaxed pieces of wood to start building from. The increased stiffness improves the tonal behaviour of the guitar as well, making the necks more evenly resonating, which eliminates dead spots. Tampere Technical University has studied Thermo Treatment for musical instruments in co-operation with a group of instrument manufacturers. The study lead to a 75-page report published in 2002, which includes lots of laboratory reasuments of various wood species before and after thermal treatment. In a nutshell – these studies show that ThermoTreatment is no “voodoo” – but a real thing.

The tone issue is a more difficult one to give simple answers to. Facts are, that resins in the wood cells vapourize or crystallize during Thermo Treatment. This is one of the crucial reasons for that the sound velocity in the wood increases – resulting as a better resonating guitar. A “new-guitar-syndrome” is very often about the lack of low mids and bass, and as a result the guitar sounds thin. We work together with many professional players, and the common opinion – shared also by several guitar magazine reviews – is that the Thermo Treated Ruokangas instrument does sound different from “just another new guitar”. It rings more – louder and better balanced.

“I just love it. The effects are very real. The treatment relaxes the wood, and the guitars just sound and behave better.” – Juha Ruokangas

thermo3Thermo Treatment was invented in Finland by Osmo Savolainen in the late 80’s. Osmo’s original aim was to find a non-poisonous yet long lasting construction material for children’s playgrounds. Later on the development continued together with Rauno Nieminen, Pertti Nieminen and a group of Finnish luthiers, and between the years 1997-2004 the optimal method to thermally treat tonewood was found.

The use of Thermo Treated tonewood has spread slowly. Ruokangas Guitars has used it since year 2000. Recently f.ex. Music Man and Suhr Guitars have started to offer roasted maple necks in their instruments. Despite the new trade name, the technology is the same, originating in Finland.

For more detailed information of Thermo Treatment and the study of Tampere Technical University, please read the ToneQuest Report article from January 2006.