The aging process

lincolnblue

I know that solid wood guitars change in time - the woods age and develop over time. I know that from guitars I have. My Breedlove for example sounds different now to when I got it almost 20 years ago. The spruce top has darkened slightly too.

I am not disputing any of that but I'm just curious to know what physically happens to the wood as it ages to change the sound of the guitar? Is it just that it dries out over time, or due to weather changes it moves slightly etc? I know solid wood ages just don't have a clue as to why

Tannin

And here I was thinking you'd started a thread about me. 

It's not drying out as such. Timber is always dried out to within certain limits before it is used for anything - even firewood! But particularly so with timbers for precision work, getting the moisture content right is a fundamental requirement before starting construction. 

Rather, it is the gradual crystalisation of flexible compounds. They harden and the timber overall changes its nature, develops more ring. Or that's how I understand the basics of the process. I'm sure that there is a lot more to it than that. 

tony99

The tiny woodworms eventually get sick of my ham-fisted playing so they leave. The little empty holes they leave behind add an airy resonance and melodic timbre to the, er, timber

bluecat

Just given you another wiz for your explanation Tannin. You always explain things in such an uncomplicated way.

lincolnblue

Tannin said:

And here I was thinking you'd started a thread about me. 

It's not drying out as such. Timber is always dried out to within certain limits before it is used for anything - even firewood! But particularly so with timbers for precision work, getting the moisture content right is a fundamental requirement before starting construction. 

Rather, it is the gradual crystalisation of flexible compounds. They harden and the timber overall changes its nature, develops more ring. Or that's how I understand the basics of the process. I'm sure that there is a lot more to it than that. 

Thanks - that's a really helpful explanation

Tannin

Cheers @bluecat - I'm laughing at @bertie's LOL!

bertie

bluecat said:

 You always explain things in such an uncomplicated way.

said no-one,  ever

Basher

Serious question: why do so many people think that ageing improves a guitar's tone?
Surely, if the sonic changes are detectable, they are as likely to cause undesirable changes as good ones?

Or is this just my innate, "dreadnaught-half-empty" pessimists world view?

I've had a decent Yamaha (L-25a) since the mid-eighties and, while I still like the sound, I have no idea if it's changed in the almost 40 years I've owned it. (Though it's probably not been played that much in the last 30, the vibrations and stresses of which must, I guess,  significantly contribute to the ageing process.)

TheOtherDennis

Can't answer your question in any technical way, @Basher, but I do know that almost any guitar shop will tell you that "Christian Martin, the current boss of Martin Guitars, has always said that the worst your Martin will ever sound is the day you buy it. It will only ever get better."

I don't think it's just marketing guff, either. Almost everyone believes it, from what I understand, so there must be something to it. At least, I've never heard anyone give the opposing view of any guitar that's been looked after, anyway - you'll get very old ones (by which I mean more than 60 or 70 years) that have aged badly because they've not been cared for, but mostly, if you look after them they repay you.

And I think a lot of people can tell because when they compare a new one to an old one, the old one almost always sounds better.

It's all a matter of opinion, though, obvs.

Devil#20

It's only as good as the person plucking the wires I've a 30 year old Martin that sounds a bit crap when I play it. My mate checked it the other day and it sounded great. Might be a weather or humidity thing. 

Tannin

Basher said:

Serious question: why do so many people think that ageing improves a guitar's tone?
Surely, if the sonic changes are detectable, they are as likely to cause undesirable changes as good ones?

@Basher I used to ask the same question. I wanted to see proper double-blind tests to investigate the matter and put any doubts to rest. After a while I realised that nobody much in a position to do that was interested simply because anyone who has built a guitar knows that it sounds dreadful at first and gets better very rapidly. (Or that's what they all say.) They regard the notion of doing "proper tests" of that as something akin to having a judicial enquiry into sunrise - just a waste of time 'coz they already know the answer.

By the time you and I see an instrument, it has done a lot of improving already as the timbers settle in and the stresses equalise. 

The real question is how much they improve after that. 

I have no doubt that several of mine have improved, at least (with a nod to @Devil#20 here) they sound a lot better than they did (say) two years ago*. 

* Today they play medium-complicated stuff very badly. Two years ago they used to play medium-simple stuff very badly. This is what I call "progress". The reality is that I always get bored playing stuff I can actually play and last about 6 bars before I'm tinkering with it, adding stuff in, trying stuff out, and making a mess, same as usual.)

goldtop

IIRC, I read that way back (before torrification/AREing/etc was a marketable technology thing) Leo Kottke used to lean his new acoustic guitar against a hifi speaker so it would resonate with the music he was listening to. He said that this would make the tone better/more defined/etc without him having to play it for hours.

So that was about vibrations in the body contributing to changes in the wood. I presume that's what @Tannin is referring to with the crystalisation thing? Whether there's scientific evidence for that, and for whether the heat/pressure treatment has the same result, I don't know.

Gassage

I posted this on another thread but will help you understand some of the things going on in timber.

This is real anorak stuff and comes from my academic cricket bat willow study in 2004 wtith Gunn and Moore and DTi....but it's key to the points you're discussing.

I apologise if it's real teccy shit.

Wood has lateral grains called medullary rays. Medullary rays are caused by plant cells that stretch away from the tree’s cells or growth rings. These carry the sap through the trunk which makes them an essential part of the growing process....resonance will be affected by if rays are full or empty of sap- I believe, but haven't proven (as this was about bats, not guitars!), that this is why guitar wood tends to mature and sound better with age.

Would add- the drier the rays, the better the resonance, or hitting power in the bat.....and the sweeter and louder the guitar will sound- why- because you're increasing resonance (ability to conduct a sine wave or, the  prolongation of sound by reflection from a surface or by the synchronous vibration of a neighbouring object.) 

Same applies precisely here.

Also, in acoustics, the modulus of elasticity (sometimes also known as Young's Modulus) of the top and elsewhere is key- MOE is expressed in pounds-force per square inch or gigapascals and it measures the ability of the timber to reform to its original shape - basically you might call this the trampoline effect-.

Tops are anisotropic (stronger in one direction than another) in nature and are flatsawn for two reasons– this puts the grain vertically where it optimal in strength and it allows the grain to offer the most elasticity. The best acoustics will perform at their best the moment before the top itself hits the moment of plastic failure (ie breaks!)- the drier the wood and the rays, the more elastic movement will occur, but sooner or later it will break as the wood becomes more 'friable'.

Finally- entropy- as the temperature of substance increases, its elasticity decreases, so for those that believe an acoustic sounds better in warm conditions, you're wrong! It can't as when the long chain molecules get hotter and vibrate, they actually shorten, causing the material to contract. When the chains cool down, they relax and stretch out, causing the material to expand.

So if you want your guitar to mature nicely, play it hard but leave in a cool dry place afterwards- allow medullary seep (drying) to occur naturally and don't try and accelerate it.

Soupman

Have a wiz @Gassage - great explanation.
 
 

DavidR

Personal views only.

 Because many are stuck on the divine properties of Martin "golden age" (mid 20's to 1940?) instruments, there's an assumption that old equates to better. Aging certainly does change the tone of a top. But I would suggest that old just means different.

New guitars can sound great but then mature and still sound great. All depends what you're liking innit. And not liking.

Also (!), when you've regularly played the same instrument for many years, as @Basher has had with that L25a, you get intimately used to every aspect of it's playability and tonal characteristics learning how to play it and how to hold it, what strings are best on it and what picks and plectrums sound optimal etc. So, unsurprisingly, the tone will improve! 'Cos you have! You've grown old with your instrument and it matches your requirements more perfectly than when you bought it.

The changing microscopic nature and changing physical properties of timber is only one factor in tone changing with time. 

drofluf

I agree with the concept that as the wood ages the tone will change over time. Whether that represents an improvement lies in the ears of the listener. Perhaps there’s an equal number old old guitars that aged badly and didn’t survive?

stickyfiddle

I doubt it's a rigid old=better situation, but I agree acoustics generally sound different once they're a few years old. I'm not certain whether that is pure age/dry-ness or to what extent it's because they've spent time under tension and being vibrated through playing.

What is interesting though is that the 2 best acoustics I've had (where best = "my favourite sounding", obviously), both of them have some form of torrefication/baking of the wood prior to building described as follows. What's really interesting is I would have dismissed this as nonsense before I bought either of them, but they're both incredible. 

Atkin: 
We started baking our tops in 2011 with the express purpose of achieving improved stability. As we’ve grown, many of our guitars are residing in countries with extreme temperatures and humidity rates, as well as traveling the world with professional musicians.

Baking reduces the moisture content and also crystallises the resins within the grain, a process that happens naturally over many years and has long been thought of as a reason vintage guitars sound so great. We also go a little bit further and bake all of our brace wood.

Bourgeois: 
Underneath the hand-sprayed sunburst lies a not-so-standard range of tonal options, beginning with an Aged Tone Adirondack Spruce soundboard. Lighter and stiffer than a traditional top, Aged Tone Spruce produces a quickness of response typically associated with years of “break-in. 

Our Aged Tone Adirondack Spruce soundboards feature an ideal stiffness to weight ratio and provide a clear, resonant tone as a result of the torrefaction process
(Bourgeois also mentioned "Aged Tone bracing & finish - i assume that's baked bracing and just a very thin nitro)

Kilgore

I wonder how much of a perceived change in tone of a guitar over the years is in part due to aging ears as much as aging wood.

lincolnblue

DavidR said:

So, unsurprisingly, the tone will improve! 'Cos you have! You've grown old with your instrument and it matches your requirements more perfectly than when you bought it.

I think that's a really valid point. I'm not saying guitars don't change and improve but familiarity with a guitar over years does make a difference. I've had my Breedlove for almost 20 years and I can tell it's changed physically (the spruce top has got a it darker) and it sounds warmer but it's like a part of me that guitar so maybe I just get better when I play it.

guitarjack66

All the guff surrounding modern guitar design sounds exactly like the same stuff around modern golf clubs. There are no doubt massive technological advancements in some areas you get the feeling only the best players will get much out of it.

Not just speaking of guitars but you always get the feeling the words are meant to soothe the fact surrounding the damage to the environment and loss of employed labour while behemoth corporations continue to make massive profits while the world suffers. This is probably just the cynic in me though.

Mellish

I've never kept.an.acoustic long enough for any aging to occur. And I think that's key cos you'd need to be with it through the years to appreciate any tonal change, surely?

I think it's around 8 years for a Martin some say.