Superior Thermowood: 'Roasted' Guitars

Superior Thermowood: An in-depth look at "Roasted" wood and its tonal implications.

Ultimate Guitar
Superior Thermowood: 'Roasted' Guitars

Today we take a look deeper into the relatively new industry term of "roasted" woods being used in guitars. "Roasted" wood is industry jargon for wood that has been thermally modified. I recently traveled to Superior Thermowood, a facility nestled among the frozen forests of Northern Minnesota. It is here that guitar parts for companies such as Gibson and Fender come to be thermally modified. I went there to learn about what exactly roasted wood is and what it means for guitarists and the future of the industry. I found the process of thermal modification and its practical and tonal implications to be an exciting new frontier for luthiers and guitar nerds alike.

Roasted wood is relatively new technology in the guitar industry but it has already unearthed a lot of great discoveries which paint a bright future for many guitarist's quest tone. What if we could build a guitar that comes off the luthier's bench or assembly line sounding exactly like a rare (insert coveted acoustic here)? What if we could make renewable woods like pine, spruce, or cedar sound exactly like or better than the more coveted exotic or endangered woods? The answer to both of these questions may lie in thermal modification.

What is "Roasted" wood?

Roasted wood is often thought to mimic the sound of vintage wood. As wood ages, it dries out. So starting out with wood that is already dried out. The process draws out the water out of the cells of the wood, leaving behind a bit for dried sap. Nearly all brands now offer roasted guitars - Martin Taylor, Fender, and Gibson.

The roasting process occurs inside a kiln - which controls temperature and humidity. The kiln at Superior Thermowood is massive. Inside this kiln is where heat and humidity, which are both closely monitored by computer, work in tandem to dry out the wood to a desired humidity level. Each wood has a specific variation of the process meant to achieve a certain humidity level, and visual aesthetic.

Thermally modified wood is used for all sorts of other applications, typically outdoor applications like decking since the wood is water resistant. This has practical uses in the guitar world - for example a maple neck that has been roasted will be more resistant to humidity changes. The same effect has been used in the past by using chemicals but the thermal modification process used at Superior Thermowood uses no chemicals. In fact, the company has won awards from The University of Minnesota for their environmentally friendly roasting process.

What does this mean for the guitar industry?

Roasting wood tends to bring out and enhance the natural beauty of the woodgrain. The color of woods can be manipulated as well. In addition to the visual aesthetic, thermal modification also enhances certain tonal qualities in the wood. It is often thought to mimic the sound of vintage wood. Whether or not roasted wood perfectly replicates the vintage sound is a hotly debated issue. The idea behind lowering the humidity level of the wood is to speed up the natural drying process. Low humidity levels are often one of the main factors contributing to the "vintage tone". One could assume that if roasted wood can perfectly mimic the sound of a vintage guitar, it could potentially drive the price of vintage guitars down. During the tour, we were able to compare pine tops that had been thermally modified against its traditional counterpart. The thermally modified top was much brighter and resonant. Another secondary effect of roasting guitars parts is that they come out lighter due to the moisture (water weight) being drawn out of the wood.

I would be remiss in my journalistic duties if I didn't mention the one obvious con to thermally modified wood - the price. Many of us who have looked into purchasing a "roasted" guitar will note the drastic spike in price when the word roasted is used. It should also be noted that different brands will use different roasting processes.

Walking around the compound at Superior Hardwood and seeing stacks of ash body blanks - ready to be sent off to Fender, Stacks of Rosewood fretboards ready to be shipped off to Gibson, its enough to have any guitar geek or DIY luthier in awe. The folks who work at ST are constantly experimenting with various woods and settings in the kiln. Somewhere between lumberjack and mad scientist, the folks at Superior Thermowood may very well hold the key to your "holy grail" tone.

28 comments sorted by best / new / date

    I was going to comment but unfortunately I slipped on some damn snake oil on my way to my desk!
    HAHAHAHAHAHAHA in all seriousness though I have a roasted maple neck on one of my guitars and it just feels and looks incredible so I guess I can't appreciate this joke as much as I really want to
    It seems reasonable to me. I don't know how it will effect tone but the idea that the wood will react less to changes in temperature makes sense.
    I've got two roasted Maple necks on my Partscasters, sounds, looks and FEELS awesome!!!
    Keyworks Kid
    This is just a gimmick to try squeeze more money out of the guitar market. There's a multitude of factors to consider when choosing the tonewood for a guitar, and while the relative moisture content of a wood is one of them, its not the end all be all of tone and its not going to make pine sound like brazilian rosewood. The "driest" a piece of wood can get is 4% moisture content, so once you're there you can't go any drier. There's other factors like stiffness, deflection, grain direction and spacing, how quarter sawn is the wood, bracing patterns, structural engineering of the guitar in question, etc. etc. Actually if anything I'm inclined to believe that scorching the grain line like that might actually hinder the integrity of an instrument over time. Not 100% on that though, just a gut feeling.
    Am I correct in thinking that "roasted" wood and "torrifed" wood mean the same thing?
    Yep. Roasted, torrified, baked, caramelised, are all different names for the same process. I'm sure various companies might use very slightly different methods, but the end result is very much the same.
    People love to get into heated debates over what affect a component of a guitar has on the tone - tonewoods, fretboards, pickups, etc. But I believe every guitar should be judged individually as a complete package. Every component has an effect on how the guitar sounds and feels, and they all interact and add up to a whole. Whether or not a special tonewood is worth the price is entirely subjective - there are really no wrong answers. The only way to know for sure is to pick one up and play it. Guitars are only worth what YOU are willing to pay.
    There's no need for things to be "hotly debated". Tonal differences can be tested for, by comparing the sound signatures of guitars that are identical in every way except the wood being used, as shown here:
    "Here is a short presentation of the results of my son's school project on this topic. For a more complete description, visit the website" So the strongest "scientific" evidence that you can present is a 13yo kid's science project? Cool.
    Any bonehead with recording equipment and the right software can generate sound signature charts from an audio signal—I don't see what age or context has to do with it. I can link a video of a 50+ guy doing the same thing if that offends you less.
    Yes anyone can do it. And they should. But as long as someone does this, and then compares different pieces of the same wood, sourced from different trees from different parts of the world, and show clear trends in how different species of wood affect the signal, this proves nothing. For all we know the differences between different wood samples from the same species are even bigger than the ones shown here. And the whole "striking the string twice" is bullshit as well, you would need a lot more, and then average the results. This experiment shows exactly nothing. So yes, tone difference can be tested, altough pretty dificult, but this is not how.
    By nitpicking on the finer points in the video showing how the tones were compared, you're highlighting how absurd your remark about it being a "13yo kid's science project" was. I'm not going to address those arguments because they have nothing to do with my premise. I used this video merely to illustrate the approach to objectively quantifying tonal differences—I could have chosen any of countless other videos doing the same, but this is the first one that came to mind. The entirety of your position here is to form straw-man arguments to undermine a comment you didn't even understand to begin with.
    So you are saying, that event tough the test is not scientifically valid in any way, it's still relevant in this context? Where is the logic in that? And i am not nitpicking, those are reasons, as to why the test proves nothing. And by saying "There's no need for things to be "hotly debated", here is this video", you are implying that it actually proves something. While it does not.
    Arrogance is an ugly trait... Why not just say "interesting video" without the patronising bite?
    I've heard that Gibson has been roasting their maple fretboards to make them look like rosewood. So you get maple tone and rosewood look. Kind of cool.