Official Luthiers Forum!

The same can be said of wood guitars. Right?
That's why we charge so much to make them.



First - I HATE the way Ovations sound, especially the carbon fiber Adamas stuff.

Second - what a boring old world it would be if all guitars sounded as sterile as an Adamas.

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"Act your age, not your shoe size" - Prince

Tai Fu, the reason I asked you to "define good sound" is because Ovation seems to be the butt of an endless list of jokes, and they are usually ridiculed and considered to be the opposite of good sounding guitars, at least on guitar maker forums such as this one. Opinions will vary, sure, but to think that Ovation would all of a sudden start producing "very good sounding" guitars of carbon fiber, should seems quite unlikely, to put it mildly, to most folks here. YMMV

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Rian Gitar og Mandolin

I don't like ovations either and honestly if someone came in with an Ovation that needed repair, I am not sure if I would be able to help. I like to see how a Carbon Fiber guitar can be repaired though, seeing how if a panel cracks, they have to be replaced.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

On the rarity of quality woods for lutherie - there are none. The rarity is the acceptance of non-traditional woods, but the consumer has been conditioned that the rosewoods, mahoganies, ebonies, spruces etc., are what constitute a quality sounding guitar.
On a daily basis I see on this forum, many examples of "non conventional" woods that are sustainable, and techniques being used to build stringed instruments. Eventually, the new woods will become more accepted by both builders and buyers, whether they like it or not.
As far as a CF Ovation goes, it would have its place, say around a camp fire, in damp conditions, or in a canoe when you've lost a paddle.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

Or as an interesting looking flower pot...

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Why has no one mentioned Rainsong, who actually build carbon fibre guitars? I have played a couple and they don't sound too bad. Being somewhat impervious to the elements I think they have a place in the guitar world.

Y'all need to seek out and try a "CA Guitars" guitar. dang fine sounding instruments!

http://www.caguitars.com/

Some Ovations can sound downright excellent, too. Tony Rice is famous for "his" tone, which most people associate with his modified/hacked 1935 D-28(previously owned by the late great Clarence White), yet on one of his most famoud, and still popular albums, "Manzanita", Tony used an Ovation for many of the songs, including the title track. Most folks don't want to believe it, but it's fact.

I see a LOT of closed-minded thinking around here..... You'll never move forward by thinking backward.

I think the carbon topped Ovations were the best sounding Ovations made. Plus you can use one as a canoe paddle. I imagine in Taiwan they could be produced cheap too since there are already many skilled workers using CF for all kinds of applications. You may be on to something

Not sure I want to work in a Taiwanese white collar environment... think wearing full body suits in 90+ degrees, 100% humidity with no air conditioning (a lot of Taiwanese factories are too cheap to use AC). I wouldn't buy a guitar from a guitar factory that has no AC for example, because it is likely that the wood will have stability issues.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Having a bunch of glues stick to carbon fiber sheet means a lot of things stick to epoxy, not carbon fiber

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

They are called opinions, OK?
Everybody has one.

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"Act your age, not your shoe size" - Prince

A wise observation from Bob.

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"Act your age, not your shoe size" - Prince

'Stiffness to weight ratio' is a _structural_ property, not a _material_ one. With decent engineering reasonably light and stiff structures can be made from all sorts of materials. Light airplanes have been made for years using all wood, wood and fabric, steel tube and fabric, aluminum, foam and fiberglass, and CF . Each material has advantages and disadvantages, and those (cost, ease of use, and so on) constrain choices more than weight in most cases. The differences _do_ matter when you're trying for very high performance, can afford top-notch engineering, and other constraints come into play. We don't usually live in that world.

IMO, the big problem with Ovations is that bowl back: it has no resonant modes that are of any use in 'coloring' the sound. There's no reason you could not get a 'flat' or normally arched back of CF to work just fine.

Back in the '70s a group from the Catgut Society worked to come up with a synthetic replacement for spruce (don't ask me why!). They ran calculations on things as exotic as corrugated beryllium (!) before somebody mentioned the 'new' carbon fiber composites. With a bit of tinkering they came up with a sandwich of about .005" unidirectional CF pre-preg skins on card stock that mimicked spruce very well. They made some guitar and violin tops out of it, and, aside from the color, the people who tried them thought they sounded fine. They ran into three problems:
1) after about three months the CF started to peel off the card stock in ribbons; probably due to the huge differential in Young's modulus beteen the core and the skin, and humidity changes,
2) it was a drag to cut the holes, and the edges were ragged, and
3) Kaman, who had been following along on the research (and provided orphan tops to the group to give them a material properties target, as did Martin), took out as patent on the thing just before they were ready to publish. Their lawyer was of the opinion that they would win a suit, but it would have cost too much, so they dropped it. I got what was left of the tops after Carleen died.

CF has such a high Young's modulus that the thickness you need for skins to be strong enough is really small. With a thin skin the supports have to be close together to avoid 'oil canning'(the difference between 'strength' and 'stiffness'). I don't see any reason you could not use CF skins and small-cell Nomex or foam to make a top. It might be tricky to get the mass down to the realm we're used to with spruce: wood is, in some respects, the 'ultimate composite'. That should not be too surprising, considering how long the 'engineering' on it has taken. If the stiffness ratio is in the same ball park as good softwood (say around 10:1), and you brace it right (or make a braceless top) there's no reason it could not sound good. The Catgut folks used the cardboard to get the damping factor up into the same realm as that of wood, and that might be an issue, but the only way to find out is to try it.

Pretty cool. While I think there will always be a place for wooden or natural guitars (and other instruments ) I think that one of the most promising aspects of a CF instrument is the possibility of a consistently good sounding yet bullet proof student instrument. CF is too expensive right now to provide that but I'm sure that some day the manufacturing methods will get to the point where a Taylor type factory can stamp them out by the hundreds for < $500 each.

That may not be good for for luthiers but it would be good for students.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Well, cardboard is wood anyways...

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Wasn't the Rainsong a carbon fiber guitar? Or was it just epoxy? I played one once - it was ok but sounded thin and, well, like a plastic guitar.

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Steve Smith
"Music is what feelings sound like"

Technically carbon fiber is plastic... its considered fiber reinforced plastic.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I've heard a Rainsong and really didn't like it at all! "Irritating" would be best description! No overtones at all. I think JJ described it best as pure fundamental in discussing Abomovations. Rainsongs are even worse than Ovations for this. They are loud or at least sound as such but not in a good way.

Carruth's "laying the body at the doorstep" of the bowl back, is lacking I believe. When looking at bracing and top construction one sees some very serious weaknesses. Just about every Ovation I've seen has a plywood top. The bracing is some kind of hybrid fan bracing that seems so inadequate as to be hard to believe. 5 little strips if 1/8" plywood fanned out through the lower bout, if I remember correctly.

Never had a chance to look into an Adamas or upper level Ovation and have heard before they sound better but what does that mean, generally?

I believe Ovation going from a thermoset glass filled(maybe denim) diallyl phthalate to carbon fiber would make no difference at all. Interestingly enough, the only real place I have seen this kind of thermoset plastic, besides the electronic fields, is in plastic model boats, because it doesn't absorb water well.

I don't believe Ovations would make a good canoe paddle because the M&T neck joint would absorb water and fail quite quickly. You'd be stuck up a creek without an Ovation.

Cumpiano, Fox, et al, have made CF topped guitars and I trust their experience to do this with competency, obviously, but I don't see a future for CF except as an auxilliary support material in serious luthiery.

Carbon fiber catches the imagination, as it should, because of it's unusual properties and there's certainly nothing wrong with all kinds of experimentation but one has to be honest about the outcome.

Never heard an Composite Acoustics guitar before and if it sounds good it would be the first I've heard. I trust in Mario's acumen but I'm struggling to believe this claim.

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

hmmm.

CF tends to come off as very fine dust, not good for the lungs, but not nearly as irritating as fiberglass that tends to come off in long shards.

For cutting tow, fabric, or uncured prepregs I suggest scissors or an exacto cutter. For cured prepregs, a jigsaw with HSS blades is very useful; as a section of the blade dulls, just add a block to move to a different section of blade.

just about any adhesive that will wet the surface will successfully glue Carbon. I have used epoxy, Urea formaldihyde, AR, polyurethane, polyester and vinylester resins to adhere carbon and carbon prepregs. If fact for working with cured prepregs, polyurethane is frequently the adhesive of choice !

-jd

interesting. I didn't try to put that picture in, I just typed the word (p i z z a)

Never heard an Composite Acoustics guitar before and if it sounds good it would be the first I've heard. I trust in Mario's acumen but I'm struggling to believe this claim

I've played Rainsongs, too, and they're very much as described. Thin, nasely, quiet, boring. But the CAs do have a surprising amount of richness in tone and rather decent power. Really! Their biggest drawback is cost, and weight. They're heavy!

As for the Ovations' bowl design not adding anything, I believe that was the original intention of both the material, and the shape/design; to minimize the body's(IE: back and sides) effect, thus allowing all the tone to be produced by the top. I don't particularly care for 'em any more than most here do, and I will NOT work on one, but I have played a few higher end, solid top Ovations that sounded really, really good. And as I said earlier, thousands of us were fooled into believing we were listening to a priceless '35 D-28 on Tony Rice's "Manzanita" album, when it turns out he played an Ovation on most cuts, including the title track.

Oh, and Ovations are a very BAD choice for playing around campfires, or taking to cold environments. Since the bowl doesn't move at all with temps or humidity changes, while the top -does- move. It either splits, or as often as not, at least in the deep cold around these parts, the top separates from the bowl!

I have a client with a CA guitar and did some work on it. It has a pretty good tone and is quite loud. Much more woody than a Rainsong or Adamas. The one I worked on was one of the early ones and it had a pronounced hump at the 14th fret. They basically had no head block in the guitar which may have caused the neck movement. I assume that they have solved that issue by now.

I would hope so.

I'm not telling anyone to go out and buy one, just saying that an all-CF guitar --can-- have really decent tone.