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I am seriously thinking about a guitar with a Koa top. A guy I know wants a very specific guitar and ... well, you know how it goes....

Anyway.... is there any general advice on building koa topped guitars? Leave the plate thicker? Make it thinner? Changes to brace strength? I am sure all of the general rules apply, but I was looking for some wisdom from those who have been down this road....

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Just curious, what is it about Koa that makes it suitable for at top. You don't often see any other hardwoods being used (with the ocasional mohagany being the exception). Shy of it's stunning looks I can't see how it would make a "better" guitar.

i've heard a few koa topped instruments and they had a very warm tone strong in the mid without undue emphasis on the bass or treble even though one was a martin koa dread. another was a taylor koa jumbo.

and the appearance is exceptional.

also saw a walnut top once, with much the same result.

The guy who wants this plays a lot of outdoor venues in the "tropical bar" scene in FLA etc. He specifically wants an all koa guitar ... I guess that is more "island-y" in his mind.

All other decisions are up for grabs, but "all koa" is a requirement.

I too, wonder how this will sound. I have played a couple of all mahogany gutiars, and 1 all walnut and I thought they had kind of a dull sound....

but I am game to try it....

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Hi Brock

First let me say I am not the greatest fan of Koa, so my view maybe a bit slanted, A friend of mine built an all Koa, it lacked punch but, it did have a very mellow and nice tone. He used his standard bracing, and we did discuss that it may be similiar to all Mahogany guitars, you should brace as light as you can get away with, as these woods are not as responsive as say Spruce, WRC or Redwood. I should emphasise this is pure theory on my part and I have never felt rich enough to try it out.

One of these days I aim to try it, too. I think that the first thing I'd look for is a well-quartered top, and I'd make it a bit thinner. Every mahogany top I've seen has been thin.
I like cherry, and I have been thinking about an all cherry guitar, too.
I liked John Denver's koa Taylors! I'm still sorry he's gone.

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Mark Swanson
Swanson Guitars
http://www.MarkSwansonMusic.com

[QUOTE=Pwoolson] Just curious, what is it about Koa that makes it suitable for at top. You don't often see any other hardwoods being used (with the ocasional mohagany being the exception). Shy of it's stunning looks I can't see how it would make a "better" guitar. [/QUOTE]

There are maple topped instruments around as well. Dean Guitars has an entire line of them.. though I think theres are veneered.

The Taylor T5 Acoustic/Electric is topped with a fine piece of curly maple from your favorite BC zoot supplier

Although I haven't heard from him in ages Bruce was also talking about doing an all maple guitar as well

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CVT Inc.
A tour of our shop (Somewhat outdated)
My Personal eBay profile. BCWoodBug

Brock,
A few months ago Bozo asked me to come to his shop to play a guitar that he had just finished. It was a small Requento 16 fret to the body all figured Koa with a ton of inlay work. He wanted to sit in front of the guitar and listen. I could not believe the balance,projection, and tone this little hardwood guitar pumped out. A great fingerstyle type sound and that was in its first few hours of life. I wonder. PS. he was satisfied and shipped the guitar to its new owner.

Brock,

I've built two guitars w/ Koa tops, one a six string, the other a twelve. I really pondered how to handle this. The wood is--as you well know--quite a bit different from spruce. First, my pieces were heavier, say 25% heavier than a typical spruce top. Then to compound things, they weren't as stiff longitudinally as a good Sitka top. Hmmm. What to do?
The notes I made at the time stated that the wood, when tapped, had a deep fundamental, with lots of overtones as well, though not as "clear" as spruce. What I ended up doing was taking the top down to .115" in the center, and thinning the perimeter a good bit. For the bracing, I used the stiffest spruce I had, and braced conventionally (no real differences in size or placement of braces). Admittedly, there was more intuition here than science!
The sound? It was wonderful, surprisingly so. Sure enough, it didn't sound like a spruce guitar, but no one cared. It didn't have the shimmery highs, or the sparkle you might associate w/ spruce. It did sound "darker". But it was a sound the owner loved...and so did I.
I think you will enjoy the experience. Keep good records of what you do, and see how your piece of Koa stacks up against the spruce you normally use. You might want to discuss with the future owner what not to expect with a Koa topped guitar.



Hope this helps some,

Steve

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

Brock, Paul Hostetter briefly talks about Koa soundboards on his site. Here's what he has to say with a link to his site below. Hope it helps.

"Koa - can be good for tops, but plain koa has always sounded better than figured koa. If you know the old koa Martins you know the good ones were style 18 with plain koa. Style 28 usually had fancier koa and generally didn't sound as good. Think tone first, then think looks."

Paul Hostetter's thoughts on wood

Thanks guys.

Steve... Those guitars are beautiful... :-)

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Brock I built several Kao toped IRW back and side OM's. Typical top thickness .100 I braced a bit lighter than I would with spruce.

The tone is more mid tone dominate so you may need to stiffen the bass side.

Koa makes a great finger style guitar with nice bass punch but the highs are not likely to be as bright as you are accustom. They are still there but the dominate mid tone tends to blend chords in to a warm melodic tone for lack of a better term. Curly tops may need filling, or the top will require more finish than you want.

I like IRW sides with Koa top. The IRW seems to brighten the tone a bit. Curly Maple bindings make this combo pop.


MichaelP38559.5141087963

Brock--thanks!

Michael--that's a real fine looking guitar! Who's the guy holding it?   

P.S.-- Michael makes a good point about the filling. I was concerned about what one maker calls the "Grand Canyon pores of Koa", so I opted to fill w/ shellac, which I thought should be a bit lighter than regular pore filler. Did that work? File it under the recent debate over bridge plates.Steve Kinnaird38559.5868634259

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

[QUOTE=Steve Kinnaird]
Michael--that's a real fine looking guitar! Who's the guy holding it?   
QUOTE]

That be my ugly mug

I filled one with shellac, one with zpoxy and one with egg whites. I like the zpoxy for the ease the best.

The top on mine..seen holding here, is very curly..too curly. The space between curls are so close and tight I think it is a bit overboard. However I have myself to blame. I got the top from Steve at Colonial and told him I wanted the curlest set he had..Well I got it. If I had it to do over I would gone with less curl

michael, as you don't like it i will gladly accept it to remove the irritation from your sight.

It may be a bit much on my eyes, but is sure sweet to my ears and it has a 14"r. FB to aid my arthritic hands. (the reason I gave up performing)...So I think I will keep it a while longer It is my favorite mid body to play It may be my favorite to play period.