What are the plus and minus's on Carbon Fiber?

[Jim K]

For me the plus side of carbon fiber is durability, NO humidity concerns, my (2) RainSongs and (1) Emerald are always available to grab and play (they sit out on stands, not hiding in cases) consequently I play more frequently, . . . and may have accidentally improved my playing!

While I very much appreciate the art represented by the appearance of a fine wood guitar, I also like the look of carbon fiber guitars alot, and happily compromise some appearance points for NO humidity issues.

After my ears quickly tuned to the sound of a carbon fiber guitar, most wood guitars sound muffled to me and uninteresting until you get to Taylors, Martins and others that are at least $2,500 and usually over $3000.

Leo Kottke states the following in an article you can find at the following link:

http://www.puremusic.com/pdf/kottke.pdf

LK: Well, actually right now I’m playing the Taylor twelve and a carbon fiber guitar made by
RainSong.

PM: Oh, I played one of those once. What’s your take on that? Well, obviously, you like it.

LK: Yeah. I haven’t had it in the studio to really hear it back, but other people have played it for me. And it has advantages, so many advantages before you consider how it sounds, that it’s almost—I have to be careful that I’m not sort of accepting the sound because of all the other advantages. It’s feather light. And you cannot hurt it. It’s carbon fiber, and very hard to do anything to it. So the case weighs practically nothing as well.

PM: And you don’t have to get a Colton case or something.

LK: Yeah, that’s right. It’s just hardly there. And it never changes. I was unaware, until this
guitar, how much I’m adapting every night to the changes in the wood. It’s certainly subtle, but I was unaware of how pervasive that subtle shift is. I’m surprised every time I pick this guitar up, because it’s exactly what it was the day before. And that it’s surprising is surprising. But you realize, “Wow, this is nice. I don’t have to make any shifts. I don’t have to get used to it tonight. It’s just what it always is.” So those are its advantages. The sound is good. And as a pickup platform, it’s excellent.

[unimogbert]

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[Jim K]

Originally Posted by unimogbert

The stability of carbon fiber is doubly appreciated when it's a 12 string.

The classic complaint about 12-ers is that you spend half your time tuning them and the other half playing them out of tune.

Not so on the carbon-fiber model.

I leave mine (CA 12 string in sunburst colors) out on its stand and haven't had to tune it in months.

But it is kind of heavy. Wouldn't be surprised if it had 2 truss rods or an iron beam in the neck as it's quite neck-heavy.

The CA guitars are notably heavier than the other brands. Try to find a 12 string RainSong to pick up and play, . . . it will probably be between 1 pound to1.5 pounds lighter than your CA. Emeralds are usually pretty light. Emerald makes a 12 string using its X10 body, which is also much lighter than the CA.

[Doubleneck]

I play a CA Legacy now as my main acoustic guitar. Advantages as said above, dead on neck that never changes. Very close sounding to wood. Rainsong Jumbo unidirectional top may be one of the best.

Disadvantages. Sound tends to be not as complex as a fine wood guitar, but it is close. CA a little heavy, Rainsong very light.

all and all I think advantages outweighs disadvantages.

[JMSparky]

What is a unidirectional top? I've seen that mentioned several times here. I'm a wood guitar player, never touched a cf guitar, but am fascinated and keeping an open mind.

[AZLiberty]

Originally Posted by JMSparky

What is a unidirectional top? I've seen that mentioned several times here. I'm a wood guitar player, never touched a cf guitar, but am fascinated and keeping an open mind.

IT means the "plys" go in one direction.

[Dru Edwards]

Originally Posted by unimogbert

The stability of carbon fiber is doubly appreciated when it's a 12 string.

The classic complaint about 12-ers is that you spend half your time tuning them and the other half playing them out of tune.

Not so on the carbon-fiber model.

I leave mine (CA 12 string in sunburst colors) out on its stand and haven't had to tune it in months.


But it is kind of heavy. Wouldn't be surprised if it had 2 truss rods or an iron beam in the neck as it's quite neck-heavy.

I'm glad that someone discussed 12 strings and the tuning issues.

[ac]

The CAs tend to be heavier by design. I've been told that this helps their characteristic more woodlike tone.

Emerald and Rainsong both make much lighter 12 strings than CA or that are possible to make with wood.

[jonfields45]

CA's back and sides use a molding process which is heavy on resin. Resin is cheap and their assembly process saves them money over carbon fabric which comes from its factory pre-impregnated with resin, such as RainSong uses. Emerald also uses raw fabric but manages to keep the resin content and weight as low as RainSong. If you attempt to flex the sides of a RainSong you will find they are a bit flexible along some of the straighter parts, which speaks to their lightest possible weight goals. I suppose none of this would contradict CA choosing their process for tone, though I never saw that claimed by them. There is a very interesting patent filed by Ellis Seal, CA founder, which unlike most patents is quite readable and informative (US Patent # 6087568).

The "unidirectional" top of RainSong's "CO" or "Concert" series means that the top visible layer of carbon fabric, instead of being a twill, has all the fibers running in one direction and looks a little like wood. Why it impacts tone, which for example the top layer of fabric in the "Black Ice" series is considered not to impact, might be because of changes we can't see underneath the top layer. One problem RainSong has as an older, but still small, supplier to the on-line music trade, is they have to be careful not to obsolete their dealer's stock. Across the board changes to all their guitars need to be subtle...

Jon

[ac]

Originally Posted by jonfields45

CA's back and sides use a molding process which is heavy on resin. . . . . . I suppose none of this would contradict CA choosing their process for tone, though I never saw that claimed by them. . . . . . Jon

I didn't mention where I go that information so want to clarify. It was not info from CA but in private correspondence with another carbon fiber luthier. His actual comments were regarding how the added mass affects and improves bass output.

One of the common gripes players have with CF is that the treble end shines so much that the bass end, even though actually very, very good, seems overwhelmed by comparison. That comparison is almost always with the standard of wood, of course.

That difference seems to 'me' to be where the closeness to the balance of wood (or imbalance, depending on perspective) comes in. I was told this added mass, for the Cargo specifically in the email correspondence I had, is one of the reasons for it's unique amount of bass for such a small package.

Subsequently, I noted that the weights of all of CA's guitars are heavier than equivalent guitars from other CF makers. It is also the consensus up to now that virtually any of the CA guitars, though heavier, have more "woodlike" tone than comes from other builders. (Though this is beginning to change.)

So the 'wood' interpretation is my own way of summarizing these observations and the listening comparisons I've done as well as spec comparisons. My thoughts are simply mine and try to reflect the whole picture. Not perfect, but I find it's a reasonable description that fits well enough for me. Varying layering techniques till now have not radically changed treble heavy guitars to guitars sounding like CAs, although there is some improvement. There may be dozens of other small factors that can affect the sound but it seems to me that mass has a bit more impact.

The reason for the mass increase affecting bass output? I leave that for physics teachers. Until I was told that, I never considered anything other than the box size in the past and the sound board. I'm sure there is a relationship and balance as simply a bigger box or increased mass can't explain everything. For example, build a tiny body out of tungsten and I can't imagine it sounding like a dread! But I could be utterly wrong--way beyond me. :-)

[jonfields45]

Though not true of CA's integrated braced models, CA's are braced like wooden guitars. Aside from the Cargo, they are X-braced. Also, the top of a CA guitar is a sandwich of materials chosen I assume to project a more wooden tone. RainSong and Emerald guitars are not braced. Ellis Seal put a lot of effort into replicating the tone of a wooden guitar, which is clearly evident when you play a CA. I have not read that patent in a while, but I think much as Torres concluded in the 1800's, the primary contributor to (CA's) tone is the top. For me, the greater projection, brighter tone, and lighter weight of my RainSong makes that work better for me, but I owned a Legacy for a while and regret having sold it... Jon