I've owned a Rainsong WS1000 carbon fiber guitar for over twenty years, and everybody who plays it says the same thing. (Usually two words, one of which is holy.) They're especially knocked out by the high end. It's crystal clear and pure, more so than any wooden guitar I've ever heard.
I wanted to discuss something surprising I discovered, a factor that nobody has mentioned yet, that arose many years ago in the course of researching this phenomena.
I found this profile of John Decker, founder of RainSong
on a physics site. (I know what you're thinking; what's that moron Forest doing on a physics site? That's like a gorilla in a knitting forum!) It's from the 90s, but something he said has intrigued me ever since.
First, a little bit about John Decker. The only reason I'm including this is so people know that the dude knows what he's talking about when it comes to physics and materials:
quote:Decker ... studied aerospace engineering at MIT, and then went to Cambridge University, where he earned a PhD in plasma physics in 1966. After receiving his PhD, Decker worked as a research physicist for the Air Force, and then moved to the Sperry Rand Research Lab in Sudbury, Massachusetts, where his research focused on plasma stability. ... In 1981, Decker moved to Hawaii as manager of the Air Force?s optical observatory. ...
See what I mean? MIT, Cambridge, multiple PhDs in physics, gummint work at high-falutin' optical thingamabobs. Smart guy.
Hang in there. I'm editing the crap outta this to get to the point, but trying not to omit anything important:
quote:?I discovered that in fact, I recognized the equations,? Decker says. They were familiar from his earlier work on acoustic waves in plasma. ?Magneto-acoustic waves, like the sound waves in a guitar soundboard, are funny acoustic waves that have different properties in different directions,? he explains.
In plasma, the direction is typically defined by the magnetic field; in the soundboard of a guitar, the direction is typically defined by the grain direction of the wood. Properties such as acoustic velocity and stiffness are very different along and across the grain. ?There?s no explicit magnetic field terms in the equations for a guitar, but the rest of it I recognized,? Decker says. ...
Okay, here we are, finally. The crux of the biscuit. Ready?
quote:Compared to a traditional wood guitar, a graphite guitar sounds clearer and brighter, especially at high frequencies.
Above about a kilohertz, wood is highly damping, meaning that vibrational energy goes into heat instead of audible sounds, so the guitar sounds ?muddy,? Decker explains. ?By the time you get to high harmonics on the high E string, what you hear is the attack, because the vibration of the top only lasts a few cycles, then damps out almost immediately.?
Graphite, on the other hand, is much less damping, giving a graphite guitar a clearer sound. In addition, because wood is so lossy, it?s inherently nonlinear, resulting in a very complex structure of missing, enhanced, and mixed overtones. Graphite is a lot less lossy, so the nonlinearities are a lot less. The result is a very crisp, well defined treble, and clarity of sound that a wooden guitar doesn?t have, says Decker. ...
Here it is again, in case you missed it:
quote:Above about a kilohertz, wood is highly damping, meaning that vibrational energy goes into heat instead of audible sounds.
Heat. Nobody has mentioned heat. And since its relevance comes into play above 1K - where upper harmonics and partials define the individual characteristics of a particular instrument - how does that damping/heat thing apply to bass?
What I mean is that if you cut off every frequency above 1K or so, you can't tell the difference between a saxophone and a buzz-saw. It's like the old grade school science experiment where if you hold your nose, you can't tell the difference between an apple and a potato. In acoustics, the upper harmonics provide the defining characteristics of a particular instrument.
And bear this in mind: in the olden days, on cold nights when Alembic owners gathered around a campfire made from Gibson basses (ptew), it was whispered that Wickershams can hear wood the same way Monet saw colors.
Perhaps that explains the brass blocks, neck-thru designs and other mass-ive characteristics inherent in our masterpieces, as well (or instead of) the vaunted sustain issue this thread is predicated upon?
They can teach us, if we behave. And I want to remind everyone that just because I raised the issue doesn't mean I know anything about it (or knitting, come to think of it).
In fact, from the moron's point of view, all I've derived from this thunderbolt of wisdom about sound waves turning into heat is that it explains why Jimi's guitars burst into flames.
Discuss.
