What will I learn?
- What torrefaction or thermo-ageing is
- How the process affects wood
- Why you would want a torrefied guitar
- Who makes these guitars
At first glance, thermo-ageing is a bit like relic’ing an electric guitar. Why would you want to make your brand-new instrument look older than it is? Well, unlike chipping paint off your precious instrument, a thermo-aged acoustic has tonal and structural benefits.
Thermo-ageing, a process otherwise known as baking, roasting or its scientific name torrefaction, involves heating wood to a high temperature to remove moisture, resin and other volatiles. Thermo-aged acoustics undergo changes in appearance, sound, weight and resilience.
You may have seen some modern electric guitars such as Music Man’s Stingray and Cutlass ranges boasting roasted maple necks. Maple is naturally light in colour, but the necks on these guitars look like they’ve been hitting the sunbeds. You can see the obvious browning effect. Thermo-ageing for an acoustic guitar yields even stronger results. Straight away you’ll notice the deeper, darker colours.
Molecules stiffen during torrefaction, providing powerful resonance and a quicker strumming response when playing. Roasted woods have an expansive EQ range and full sustain. They’re even louder than their non-aged equivalents across the frequency spectrum, especially in bass and treble.
An acoustic must stay slightly hydrated to keep its good condition. No, this doesn’t mean chucking water over it, but keeping it out of hot/cold places or avoiding a quick change in temperature. When a guitar dries out, the wood contracts and cracks may start to appear from the glue working overtime to hold it together. A guitar is less susceptible to these atmospheric effects following torrefaction.
The treatment fast-forwards the natural ageing process. It can’t improve bad woods but does bring out vintage properties in good pieces. Valued old acoustics are extremely sought after because they become chemically balanced and more stable over a long period of time. So if you’re on the hunt for a retro guitar tone but aren’t prepared to fork out for vintage prices, roasted guitars are a realistic option.
There’s plenty of choices too. Several tonewoods are capable of being baked, such as maple, mahogany and spruce. It’s still possible to get varying tones after the process has been completed. However only choice-selected and seasoned woods can undergo it.
Ibanez are one of the latest guitar builders to take on the roasting challenge. Despite being obviously well-known for their electric guitars, they’ve boldly released a thermo-aged line of acoustics all well under £1000.
The range features a host of thermo-aged choices. You can get your hands on a number of spruces and mahoganies, in combination with X bracing that further boosts volume. They say some of the guitars are ‘open pore’ which refers to the satin raw finish, but in fact, they tighten up through treatment. They look older as well as sound vintage.
Most heavyweight acoustic companies such as Gibson, Taylor, Martin and Takamine have used torrefaction to great effect. Many custom shop or high-end acoustics undergo baking because it’s a proven scientific process that can heighten the properties of wood.
The downside is you’ll be looking at £2000 upwards for these guitars. Check out Gibson’s 2019 Montana range to get an idea of specs and style. They’ve been pioneering it in the Vintage series of guitars for years. Taylor’s 600 Series is also a perfect example of torrefaction taking a guitar to the next level of brilliance.
The likes of Yamaha, Ibanez and Takamine, however, produce excellent thermo-aged guitars at a significantly reduced price in comparison. To be able to get your hands on a mid-range guitar with such a defining feature used on custom guitars is a testament to the market offering progressively better specs at similar prices.
If you enjoyed this, have a read of our other Learn articles on the Andertons blog!