Previously in Part 1 (Softwoods for Acoustic Guitar Soundboards)…
We explored why softwoods like Sitka, Lutz, Engelmann, cedar, and redwood are the heart of an acoustic guitar’s voice, defining responsiveness, projection, and touch sensitivity.
Now, we turn to another facet of the story…
If the soundboard is the “speaker” of the guitar, the back and sides form the speaker cabinet. These parts, typically made from hardwoods, shape the tone by adding their own resonance and reflecting sound inside the body. The guitar’s back and sides vibrate in line with the top, contributing to overtones and sustain, but they also primarily act as reflective surfaces that color the sound.
Continuing our conversation with Steve Nall (aka Nully), Head Luthier and Director of Manufacturing at Collings Guitars, and Rye Bear, Luthier and Founder of G. R. Bear Guitars, we now asked them about hardwoods.
Rye explains this importance with exceptional clarity:
“The sides are actually the second most influential component of the guitar. If the sides are stiff and strong, more vibration gets reflected back into the top. If the sides are flexible, energy spills into them, and you get a more percussive sound.”
This is why he sometimes laminates sides to make their behaviour consistent and to remove unpredictable absorption from the acoustic equation. His approach highlights an often-overlooked reality that backs and sides do more than “shape” tone; they help define the dynamic behaviour of the instrument.
At Collings, Nully sees the same principle but from a different angle. For him, backs and sides must complement the top, not contrast it.
“I’ll hear luthiers sometimes say that the top is 80% of the tone. And I don’t 100% agree because then why is everybody buying Brazilian rosewood if you can get mahogany for a hundredth of the price? Because it sounds different. So, then the top isn't 80%. They're all just different.”
Hardwoods for Backs & Sides
1. Rosewood
Rosewood has long been a gold standard for high-end guitars. Some examples are Brazilian rosewood (legendary on vintage guitars) and East Indian rosewood (the most common modern substitute). Rosewoods are very dense and hard, with a high velocity of sound, which means they transmit vibrations quickly.
A rosewood body typically yields a rich, complex tone with deep bass and chiming treble overtones. In fact, these guitars often have strongly pronounced low frequencies (sometimes described as a “boom” or rumble), as well as sparkling highs, giving an expansive frequency range. The plentiful overtones produce what many players call a “reverb-like” ambiance or natural echo in the sound. Indian rosewood is slightly less dense than Brazilian but still provides plenty of warmth and overtone content. Brazilian rosewood (now very scarce and expensive) is praised for its exceptional clarity in the bass and bell-like trebles, essentially “rosewood plus more of everything”.
It’s important to note that solid rosewood guitars can be quite heavy, and the wood’s open pores require careful filling and finishing. Overall, rosewood backs and sides give a luxurious, piano-like tone loved in styles like fingerstyle, folk, and any music where a lush sonic depth is desired.
2. Mahogany
Mahogany is another classic tonewood, used on countless guitars like pre-war Martins to Gibson acoustics. Unlike rosewood’s complex overtones, mahogany is loved for its dry, direct sound with strong midrange focus. It’s somewhat less dense than rosewood and has a lower velocity of sound, which yields fewer low-end overtones. You get what is often described as a woody, punchy tone with clear note definition.
Mahogany-bodied guitars excel in midrange warmth; chords have a smooth balance, and single notes have a strong fundamental and quick decay. You won’t get the booming bass or glassy treble overtones of rosewood – instead, mahogany’s voice is more about clarity and earthy warmth. This makes it a favorite for blues, country, and many recording applications where a controlled tone is preferred.
Historically, mahogany was used on “workhorse” guitars (for example, Martin’s D-18 has mahogany back and sides, versus the rosewood D-28). It’s generally more affordable and very stable to work with, which also contributed to its popularity.
Fun fact: Many vintage recordings (e.g., old blues and early Beatles acoustic tracks) feature the fundamental-rich sound of mahogany guitars.
3. Maple
Maple is a hardwood known for its use in violins, cellos, and archtop guitars, but it also appears in flat-top acoustics (Gibson jumbos, for instance). It’s extremely hard, dense, and has a very low internal damping factor. This basically means a maple back and sides do not add a lot of overtone coloration to the guitar’s sound, but they reflect sound very efficiently and have a quick decay.
These guitars are famous for their bright, clear, and “transparent” tone, often described as highly articulate. They tend to emphasize the fundamental note and have a fast response, which can help complex fingerpicking arrangements remain separate and clear. Because maple doesn’t naturally boost bass or treble heavily, it can result in an overall balanced EQ with a slight midrange focus. Some describe maple’s tone as “clean” or even “shallow” compared to rosewood or mahogany, but in ensemble settings, this clarity helps the guitar cut through.
Flamed (figured) maple, besides looking beautiful, is a prized wood for its consistent tonal response and sustain. Notably, bigleaf maple from the Pacific Northwest is used by many makers.
At Pacific Rim Tonewoods, we're at the early stages of propagating figured maple to add value and diversity to our forests and ensure a sustainable supply for luthiers.
4. Koa
5. Other Hardwood Options
Beyond these traditional species, luthiers continue to explore alternatives that offer unique tonal character and sustainable sourcing.
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Walnut produces a tonal response somewhat between mahogany and rosewood, generally clear and bright with moderate overtones (some call it a more neutral-sounding tonewood).
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Cherry is a domestic wood that has a warm, mahogany-like tonality with a pleasant midrange and slightly soft high end.
- Sapele (often used as a mahogany alternative from Africa) and ovangkol (used by makers like Taylor) offer tones in the rosewood-family spectrum, with ovangkol having a little extra midrange fullness.
Each hardwood brings a different harmonic fingerprint, and in skilled hands, each can support an expressive, beautifully voiced instrument.
A Closing Note on Hardwoods & Character
Hardwoods don’t shout at the player the way soundboards do, but they absolutely shape the experience of the instrument. They influence sustain, projection, overtones, and even how the top behaves under attack.
Or as Nully puts it:
“You can’t make mahogany sound like rosewood, and you can’t make rosewood sound like mahogany… they all do their own thing.”
For all their tonal influence, backs and sides remain part of a larger whole. They shape, reinforce, and color the energy created by the top. When you pair them thoughtfully and match for weight, stiffness, stiffness-to-weight ratio, and vibrational behavior, they elevate the guitar beyond the limits of any single piece of wood. And in the hands of an experienced luthier, these hardwoods become not just structural components, but resonant partners in the guitar’s voice.
If you’re exploring back and side sets that bring beauty and tone together—including figured maple, koa, walnut, and more—you’ll find the finest figured maple and koa back and side sets here in our hardwood tonewood collection, plus rare limited runs in the Vault.
Up next in the series: Part 3 — Fingerboards & Pairings, where we continue our tonewoods journey with Nully and Rye; this time, talking about how fretboard materials and tonewood combinations influence balance, feel, and the final voice of a guitar. Stay tuned!
