Listening Tests: Tone-Woods

Fair warning: This post contains pie-charts. ;-)

It’s worth it though. Honestly. This is stuff that every musician should be aware of.

I’ve long been interested in how our weird, flawed, squishy brains can make weird, flawed, and erm… squishy decisions for us. The things we think we know colour the things we actually experience. It’s fascinating really.

And, the world of musical instruments is a hotbed of squishy-brained preconceptions.

Take tone-wood, for instance.

Which is just what The Leonardo Guitar Research Project did.

What the heck’s The Leonardo Project thing?

The Leonardo Guitar Research Project is a non-profit group of European luthiers and lutherie schools. Their goal is to study and demonstrate the possibilities of building acoustic and classical guitars from non-tropical woods.

That’s a mouthful so I’ll give you some context.

The ‘Tradition’

For a very long time, we’ve made some wonderful guitars out of beautiful, exotic woods. Tropical woods like rosewood and mahogany are probably the most commonly used.

And, like anything that’s done a particular way for a long time, we eventually accept that this is the way it should be.

We see a guitar with a back and sides made from a plain, locally-grown boxwood and we dismiss it as inferior.

Wait. What’s that you say—I should actually listen to it before dismissing it? Oh, ok then.


OK, I’ve listened. It’s no good. Now where’s that Brazilian rosewood guitar?

The catch

Ah. Turns out, that might have been a ‘squishy’ decision.

We are all at the mercy of our biases and preconceptions. We think we’re all Johnny or Jenny Smarty-Pants, but we’ve all got brains trying to make shortcuts to a decision that fits us perfectly.

The Leonardo Project people set out to see if this might the case for tropical woods.

The experiment

What they did was to build fifteen classical guitars of the same type (based on a Torres FE19 model). All fifteen used equivalent quality European spruce for tops and braces. The sides and backs of five instruments were of traditional, tropical woods and the other ten were each a different, non-tropical (and therefore 'non-traditional') wood.

The build process was carefully controlled to ensure each was as alike as possible. The neck and fingerboard sizes and shapes were duplicated carefully and each was set-up to play identically.

Then, they tested them.

There were a few different tests but I’ll just summarise the player and listener ‘pair’ tests. The guitars were tested in pairs—one tropical wood and one non-tropical—with a guitarist and a listener.

The results

Well, pretty much as you’d expect, I suppose.

On average, 78% of the guitarists preferred the guitars made from tropical wood. 72% of listeners also preferred the tropical instruments.

Listening Tests - Tropical Vs. Non-Tropical Woods

Back to the drawing board?


We have to take our squishy head-meat out of the picture.

We have to BLIND the test.

If we can see the damn things, our preconceptions nudge us to their side without our even realising. But what if we can’t see?

That’s much more interesting.

If the player and listener are both blindfolded and are unaware if the instrument is tropical or non-tropical, things are a bit different.

Listening Tests - Tropical Vs. Non-Tropical Woods - BLIND TESTING

When blinded, only 53% of guitarists chose the tropical wood instruments and only 47% of listeners did.

And, when these results are bundled with LGRP’s other blinded listening tests, the aggregate results come in right down the line at 50:50. Check the Leonardo Guitar Research Project site for additional test information and to show I’m not cherry-picking.

What does it mean?

To quote LGRP, “Experienced guitar players and listeners were unable to distinguish tropical from non-tropical at better than chance levels. All blind tests show that it is possible to make equally good sounding guitars from both Tropical and Non-Tropical Woods.”

The emphasis is mine because it's important. This is something we should all consider.

When people knew they were hearing a non-traditional guitar, they were more likely to prefer the other choice. When they couldn't see the instrument, there was no bias and there was no preference either way.

We musicians have a lot of sacred-cows. We have a lot of ideas of what must be present to get the right tone. It’s got to be that name on the headstock, and that wood, with that string, that pickup, and that capacitor. We need that lead and that slightly-dying battery in our pedal.

Some of these may be valid. Bear in mind, though, that some may be myth-buster material if we have to listen blinded. If we don’t know whether component A or B is present, will we always make the decision we believe we will?

Interesting thought, isn’t it?

Note #1: Non-tropical woods used were: alder, oak, walnut, beech, ash, birch, chestnut, plane, boxwood, robinia. These were used for back and sides. Also some of these woods were also used for necks, fretboards, bridges, linings, and neck/end-blocks.

Note #2: All of this is important because the tropical woods we love are getting much more scarce and very much more expensive. They are increasingly subject to trade restrictions (and as a consequence are more at risk of illegal harvesting). Having sustainable alternatives that still sound great is fantastic news.

Note #3: Incidentally, my fellow countryman, the kind and talented Chris Larkin, is a member of the Leonardo Project. Chris has long been a champion of non-tropical and local woods, and he makes some really splendid instruments from them. You should check him out.