Interesting. Never heard that before but I will say that I've played on a few 100+ year old guitars over the years, and all the ones I've played had a dark, woody, sort of tone to them. Then again guitars that old usually have gut strings on them, since they're not built to handle steel strings, so that probably has a lot to do with it. Even still, they sound darker than say a modern classical guitar. Not sure why.
Great post supported with scientific data.The notion that age affects instruments in beneficial ways has been more folklore than evidence-based. It had a big setback when modern masterbuilt violins were mostly preferred over revered old ones by experts in a series of blinded studies.
Regarding the mentioned exposure of acoustic guitars to artificial vibrations, the only real controlled study showed that it did not work. No measurable changes were found, and experienced guitarists could not reliably pick the "treated" guitars.
Clemens et al. (2014). Effect of vibration treatment on guitar tone: A comparative study. Savart Journal, 9. https://www.savartjournal.org/articles/22/about.html
João Pedro de Aragão Alegria Oliveira. (2018). Evolution of the vibrational behaviour of a guitar subjected to localized vibratory excitation [Master of Mech Eng Thesis]. Universidade de Coimbra.
There are a number of patents on vibration technology for musical instruments, but patents require no proof that inventions actually work.
If it doesn't happen in obvious ways for acoustic instruments, it's hard to see it happening for solid body electric guitars. But studies in electric guitars are very rare, and very limited in scope. eg
Esposito, E. (2003). A comparative study of the vibro-acoustical behaviour of electric guitars produced in different decades. Proceedings of the Stockholm Music Acoustics Conference (SMAC 03), 125–128.
Guitar manufacturers mostly use seasoned wood that has reached a low moisture content, often over considerable time. Mostly to ensure neck stability. Since no one made controlled recordings of now-vintage guitars when they were made, to compare to how the same guitar sounds today, we'll never know for sure. It's likely that there's a healthy dose of simple nostalgia/romanticism about "old wood" aging gracefully. Particularly since measured evidence from real electric guitars suggests that the reasons for their sonic differences lie in places other than the body wood.
The Physics of E-Guitars: Vibration – Voltage – Sound wave - Timbre (Zollner)
If there are any sonic changes over decades, it's possible that they could be due to other things. Maybe micro-shorts in pickup coils as the insulation degrades. OTOH there is little support for magnetic changes from pickup magnet experts.
We definitely hear things differently from day to day, and mood can affect our perception even beyond that.Sound seems subjective at times, to me. There are days when I plug in, same settings as the day before, and I just don’t like the sound which was fine the day before. Can’t really explain what it is - but it’s very likely me and not my rig.
Electric guitars do sound better when they're played more; it's called practice.I used hear and read about this - only on acoustic guitars, that they get sound better as they get played more.
If that is true, would it be the case for electric guitars too? Or it doesn't make sense?