IRYW : Guitars don't age like wine

A guitar does not open up.

Wine does, and it's worth being precise about why, because the comparison gets repeated as if it explained something. A bottle ages through chemistry: tannins polymerize, esters form, a trickle of oxygen rearranges what's in the glass over years. A wine "opens" in the decanter through a faster chemistry — aeration, volatiles leaving, oxidation beginning. Two mechanisms, both measurable, both with reagents.

I know that because I'm French.

A guitar has neither. There is no reagent in a spruce top, no reaction that playing initiates. What the guitar has is a player, a set of strings, a setup, a room with weather in it — and a brain that was always going to find what it was told to find.

The playing-in debate has been argued on the wrong axis for a century: how much playing, how many hours, which notes, which device. The right axis is simpler. Where does the change happen — in the instrument, in the hands, or in the head? Until this year, nobody had measured all three at once. And there's a second question nobody asks, because the answer is embarrassing: on a human timescale, which direction does a guitar actually age?

Nobody Move

In May 2026, Acta Acustica published a study from the Institut Jean le Rond d'Alembert at Sorbonne Université — Hugo Pauget Ballesteros, Philippe Lalitte, Vincent Lostanlen and Claudia Fritz, the same Fritz who ran the blind Stradivarius tests. The title is the whole argument: Violin "playing-in": disentangling physical change from player adaptation via physical measurements.

The design is the point. One professional soloist chose a rarely played 2012 violin because he believed it could open up, and played it daily — not for a fixed period, but until he reported that it had. That took about six months. Two comparable violins, one built the same year with similar construction and varnish, sat in the Paris Conservatoire's collection as controls. Ten other violinists, blind to the roles, recorded standardized excerpts on all three, before and after. Bridge admittance was measured with a laser Doppler vibrometer; the soloist's bowing was tracked with twelve motion-capture cameras.

The result is what the authors call a double null. The played violin's frequency response after six months sat on top of its response before, and the small differences were the same size as the drift in the two violins that had been sitting in a cupboard. The control players' recordings told the same story. And the soloist's bowing hadn't changed either — his technique on the test violin varied no more than on his own instrument.

He said it opened up. The laser didn't notice. Neither did his bow arm.

Patient Zero Was Italian

The belief is older than the industry that sells it. Players have been saying old Italian violins "sweetened" with use for as long as there have been old Italian violins, and the idea that an instrument is finished in the hands rather than on the bench has a romance no measurement will kill. It flatters the player: your years are in the wood.

The modern, scientific-sounding version has a specific origin. Carleen Hutchins — the New Jersey science teacher turned violin maker who dragged violin acoustics into the laboratory in the 1950s and 60s — hung instruments in a vibration chamber in her basement; the 1962 Scientific American cover painted exactly that. In 1998 she published "A Measurable Effect of Long-Term Playing on Violin Family Instruments" in the Catgut Acoustical Society Journal, and the violin world had its citation. Her work is foundational and I'm not going to be snide about it. But those early studies, as the Paris team notes, lacked unvibrated controls and blinding — so they couldn't separate a playing effect from a humidity swing or an experimenter's hope.

Then commerce arrived with a plug. ToneRite — patented around 2010, first built by its inventor to break in his own cello — sits on the strings near the bridge and hums into the instrument for a recommended seventy-two hours. Guitar reviews started using "opened up" the way wine writers use "developed." Factories learned to roast tops and sell the result as decades of aging in advance. A folk belief had become a product category, and a product category needs the belief to be physics.

Control Group: Vibes

Here is what a player actually compares when he says his guitar has opened up: the guitar on the day he bought it — shop strings, shop setup, shop humidity, twenty minutes in hands that didn't know it — against the same guitar a year later, with his strings, his setup, his room, and a few hundred hours logged on that exact neck. He then attributes the difference to the wood.

Nothing in that comparison is held constant except the serial number. No control guitar, no blind, no day-one recording under matched conditions. His control group is his memory, and memory is the least reliable instrument in the room. Vol. IV went through this with tonewood and Vol. V with looks; the mechanism is identical. The player isn't lying. He's measuring with the wrong tool.

A comparison of the same guitar across a year is a comparison of two different years.

Microfibrils or Midi-Chloriens ?

Stated as charitably as I can: the claim is that the low-amplitude vibration of playing does something cumulative and permanent to the structure of the instrument. Drying stresses relax, glue joints and finish "settle," cellulose microfibrils align to the direction of vibration, the top "loosens up." The argument isn't stupid — wood is viscoelastic, it creeps and relaxes, and vibration interacts with that. The question is whether playing-level vibration does enough of it, permanently, to change what comes out of the soundhole. That's an empirical question, not a philosophical one.

Openness Is Not a Unit

For an instrument's sound to change, one of a short list of things has to change. The resonant frequencies of the body, set by the stiffness and mass of the plates and the air inside them. The damping — the mechanical loss tangent, tan δ, which is how fast the wood turns vibration into heat. Or the geometry: arch, bracing, joints, string height over the body. That's the whole list. There is no fourth property called "openness."

Now the amplitudes. A played top moves on the order of hundredths of a millimeter, and the strains inside the spruce during the loudest strum are tiny — far below anything that rearranges a cell wall, far below the loads that make wood creep measurably. The material has no idea whether it's being vibrated by a Bach partita or a washing machine; it sees amplitude and frequency, and both are small. Wood changes structure by three routes: chemistry over decades, heat in an oven, and water. Vibration at playing levels is, at most, a footnote to the water.

And that's the generous case, an acoustic, where the top is the loudspeaker. On a solid-body electric the pickup reads string motion and the body enters only as a boundary condition at the bridge and the nut; Vol. VII covered why. If the effect can't be found on a violin top, it has nowhere to hide in a slab of ash under a humbucker.

Okay, a Few Hertz

Honesty is the whole point of this series, so: there is lab evidence on the other side, and I'm not going to pretend it isn't there.

Daniel Hess, a mechanical engineering professor at the University of South Florida, published frequency-response measurements in the Savart Journal in 2022 showing changes in new acoustic guitars after 168 hours of broadband vibration — resonance peaks gaining magnitude and sliding slightly lower — which he reads as vibratory stress relief. A 2015 conference paper from Eiichi Obataya's wood-physics group at the University of Tsukuba reported that continuous vibration slightly lowered tan δ in wood specimens, with relaxation of drying stress as the proposed mechanism. And in 1996, D.G. Hunt and E. Balsan published a short piece in Nature titled "Why old fiddles sound sweeter," on vibration interacting with humidity cycling in spruce.

So something can happen to wood under vibration. What these results don't show is that it happens at playing amplitudes, that it persists, or that anyone can hear it. The Paris authors, summarizing this literature, describe the effects as tending to be reversible or dependent on extreme humidity. Hess's instruments were shaken, not played, and nobody listened to them blind; Obataya's numbers come from specimens, not guitars. A peak shifting a few hertz in a plot is a measurement. "My guitar woke up" is a different claim, and the gap between them is where the myth lives.

Stanford Brought a Hammer

The guitar-specific test already existed. In 2014 a Stanford group led by materials scientist Bruce Clemens, with Jay Kadis of CCRMA, published "Effect of Vibration Treatment on Guitar Tone: A Comparative Study" in the Savart Journal. Three pairs of guitars, each pair the same make, model and year; one of each pair treated with a commercial vibration device, the other left alone. Double-blind player evaluations before and after, plus frequency response functions from instrumented hammer strikes. Neither the players nor the hammer found a significant change in any pair. The treatment had done nothing measurable to the tone.

The twin study ran longer. At the University of New South Wales, Ra Inta, John Smith and Joe Wolfe commissioned Sydney maker Harry Vatiliotis to build two violins in parallel from matched wood. One went to a professional who played it regularly; the other went into the Powerhouse Museum and was rarely touched. After three years, panels of experienced violinists played and listened to both: no significant preference on any category measured. In 2024 Andrew Piacsek and Seth Lowery tested mechanical playing-in devices on a new violin and, by the Paris team's reading, found the same nothing.

That's the state of the evidence. Decades of testimony with no controls, versus every controlled test coming back empty. That doesn't prove the effect is zero — science doesn't do that. It does mean the burden of proof has changed sides, and it changed sides a while ago.

Pre-Opened

Everything a player feels "settle" in year one can be engineered to arrive settled. That's not a slogan; it's a checklist. A neck that holds its geometry — carbon fiber or titanium alongside the truss rod — doesn't spend six months finding its relief. Frets leveled under string tension on a PLEK machine have no break-in period, because there's nothing left to wear flat. A nut cut to the gauge on day one doesn't need the strings to saw their own slots. A thin polyurethane finish is cured when it ships; it won't keep shrinking into the grain for a decade the way nitro does.

The honest translation of "it'll open up" is "the setup isn't finished." On an instrument where the setup is finished — intonation corrected, action and relief set to the player, strings fresh — what's left to open is the player.

Hard Case Studies

A player buys a guitar, dislikes it for a month, and loves it by month three. In between, the shop strings died and got replaced with his gauge, a tech dropped the action a hair, and his left hand learned where the neck wants his thumb. He credits the spruce. The spruce was not involved.

A workshop runs a vibration box on every instrument for seventy-two hours before final setup, and the instruments leave sounding great. The box gets the credit; the setup that follows it does the work. There is no version of that workshop where the box runs and the setup doesn't — the exact confound Clemens designed around.

A collector owns a 1958 archtop and will tell you it has opened like a flower over sixty-eight years. Its nitro finish has been shrinking since Eisenhower, it's had three sets of frets and two neck resets, and not one person alive heard it new. No one can put the 1958 version and the 2026 version in the same room.

It's You. It Was Always You.

The Paris study's quiet landmine isn't the admittance curves. It's that the soloist's bowing didn't change either. The obvious escape hatch — "fine, the instrument didn't change, the player adapted" — closed too, at least at the resolution of twelve cameras. So what opened up?

The authors point to the mere exposure effect: the well-documented tendency, going back to Robert Zajonc in the 1960s and shown for music by Isabelle Peretz and colleagues in 1998, to rate a thing more highly simply because it has become familiar. You liked the guitar more on day 300 than on day 1 because you had heard it 299 more times, and familiarity is processed as quality. Add expectation — an established maker had told the soloist he was "the perfect candidate for opening a violin" — and the experience is fully explained without a cell of spruce moving.

Piacsek and Fritz surveyed musicians and luthiers in 2025 and, in preliminary results, found over seventy percent still convinced the effect is physically real. Seventy percent of a trade can be wrong about a mechanism while being right about the experience. Both halves of that sentence are true, and the second half is why the first half survives.

Go Fund Yourself

A six-month study with one violin and one soloist is a strong result, not a final one, and the authors say so. Another instrument or player might behave differently. The small admittance changes they measured — the same size on played and stored violins — might still matter to a listener; the perceptual ratings and blind recordings exist and are headed for a second paper. And their motion-capture analysis is macroscopic; adjustments below its resolution are possible.

Nobody has run the guitar version at scale. The study that should exist: twenty matched pairs of acoustic guitars from the same batch, one of each played daily for twelve months, the other stored alongside it with logged humidity; bridge admittance and radiated spectra every three months; a blind ABX panel at the end, because an FRF that moves and a listener who can't tell are two different findings. Run it with electrics too. Until then, the honest answer to "do guitars open up" is: every time someone has looked carefully, no.

Am I Right ?

There's a real concession to make, and it's bigger than usual. Wood ages — not metaphorically, chemically. Takunori Noguchi, Eiichi Obataya and Kosei Ando compared wood between 121 and 296 years old against eight-year-old stock and found the old wood had higher sound velocity and lower damping, which they attribute to cellulose crystallizing, hemicelluloses breaking down and lignin cross-linking over centuries. That is a measurable change in exactly the properties that govern tone, and it happens with the instrument sitting in a case. Obataya's 2017 review in the Journal of Cultural Heritage adds a detail worth keeping: naturally aged wood and oven-treated wood are not the same material. The roasted top is a different shortcut, not a time machine.

Humidity is real too — moisture content moves stiffness and damping, reversibly, and a player who feels his guitar change between seasons is feeling physics. A nitro finish really is still, slowly, becoming a different object. And the player really does learn an instrument, even if the Paris cameras couldn't see the bow arm doing it; on a fretted, plucked instrument the learning may live in the right hand, which nobody has tracked yet. A carved archtop top — the one format on my bench where the century-scale chemistry has a real channel — will be a different piece of wood in 2226.

Here is the limit of the concession. The chemistry happens over a timescale you will not be alive for. The humidity effect is seasonal and reverses. The finish effect is the finish, not the wood, and it vanishes on a cured modern coating. And the aging that is real comes with its own inconvenience: Claudia Fritz's blind tests — ten soloists in 2014, then concert audiences in Paris and New York in 2017, both in PNAS — found that neither players nor listeners could tell old Italian violins from new, and on balance preferred the new. The aging is real. The preference isn't. None of it is vibration. And the aging you can see with your own eyes, on a timescale you'll live through, runs the other way.

Entropic Truss Rods

Set the wood aside and look at the rest of the instrument, because the rest is not debatable. A guitar is a structure under permanent load. Depending on gauge and instrument, the strings pull with somewhere between fifty and eighty kilograms, every hour of every day, for decades — and wood under sustained load does the one thing the playing-in crowd keeps hoping it will do: it moves. The neck creeps forward until the truss rod is doing all the work. On a flat-top, the top bellies behind the bridge and the neck angle drifts until, a few decades in, the instrument needs a reset. On an archtop, the bridge presses straight down into the top, year after year. None of that is the instrument opening. It's the instrument losing a very slow argument with physics.

Then the parts. Frets wear into divots, get leveled, get leveled again, get replaced. Nut slots deepen until the open strings buzz. Tuners develop slop; potentiometers go scratchy, switches oxidize, capacitors drift, jacks loosen. Celluloid pickguards shrink, warp and, on some vintage instruments, quietly off-gas acid into the hardware around them. Binding cracks, nitro checks and yellows, a glue joint lets go under a brace. Every humidity cycle shaves a little more off the fingerboard until the fret ends stand proud. This is what aging actually looks like on a guitar, and all of it points one way.

So the ledger reads like this. Acoustically, on any timescale you'll experience, the instrument does not improve — the controlled studies can't find it, and the century-scale chemistry that is real comes with no audible preference attached. Mechanically, it only degrades, and the degradation is measurable with a straightedge and a feeler gauge. A fifty-year-old guitar that plays beautifully is not a guitar that aged well. It's a guitar that was maintained well — a different achievement, with a different person's name on it.

The instrument doesn't open up. It wears out, and someone keeps fixing it.

No Futures Trading

What this changes in practice is the purchase. Don't buy potential. The Paris authors draw the conclusion themselves: if good instruments are physically stable and don't force the player to adapt, buyers should trust their first assessment, and buying for a promise to open up is a bad heuristic. A guitar that doesn't sound right in the shop is a guitar that doesn't sound right. Buy the one that does.

Then do the things that actually change the sound. Change the strings before you judge anything. Get the setup finished — relief, action, nut, intonation — in the climate the guitar will live in. Play it, not because the wood needs it, but because you do. Three hundred hours from now it will sound better to you, and it will be you.

La Conclusion S'il Vous Plaît

Playing doesn't change wood at playing amplitudes on any timescale a player can experience, and every controlled test that has looked — twin violins over three years, matched guitar pairs with a vibration device, and now six months of daily playing under a laser in Paris — has found nothing beyond environmental drift. The lab results that do show vibration touching wood are specimen-level, unblinded, and described by the people who know the field best as reversible or humidity-dependent.

What "opens up" is the setup finishing, the strings being replaced, and above all the player's familiarity being misfiled as the instrument's quality. Meanwhile the parts that do age — the neck under load, the frets, the nut, the finish, the electronics — age in one direction, and it isn't the one in the brochure. Guitars don't age like wine; wine has chemistry. Guitars have owners, and owners have repair bills.

I'm right. And you....

Buy the guitar you like, the rest is just going downhill

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