Official Luthiers Forum!

I know that there are different species of woods that are typically used for back & sides that are used for tops, like; koa, mohogany, and maybe monkey pod. Are there some other kinds that are typically used for back & sides that make good tops and what are their attributes? Never mind about the usual tops, i.e. spruce, cedar, redwood...

Just wondering... in case I want to build one of all the same wood...

_________________
Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Steve Myrtle is another that some folks use for tops.

From the lack of response, I take it that there is not much enthusiasm for using other than the usual suspects...

What about redwood... I've heard mixed things... It sure can look pretty and LMI's description sounds nice, but can't it be kinda tricky?

_________________
Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Redwood is a spectacular top wood. IMO much more complex in tone than WRC But I would not consider Redwood an unusual or alternate top wood as it has been used on classicals for a hundred years or better.

The tricky part is the handling as it is easy, easy, easy, easy to ding up during construction. Outside of that it is easy to work with.

Redwood is widely used as top material by many builders now, it is very close to WRC in tone and general characteristics. It is also very brittle (splits and checks easily). Maple has been used for the top on some French and English guitars from the 18th century, people who've listened to the still playable instruments did not write enthusiastically about the tone though.

_________________
Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Here is another question for the gang...

if you were going to use myrtle or maple or some other hardwood for a top, what thickness would you suggest?

_________________
Reguards,

Ken H

Koa, Mahogany and Maple I use .110 as the starting point.

Thinning to a predetermined deflection is really the only way to figure out.

I can't imagine using a wood like maple or myrtle... they both have such high internal sound damping. First and foremost I would think you want the topwood to ring.

What about Taz Blackwood?

Sure - not unlike using Koa for a top.

Actually, maple doesn't have much higher damping than most spruces, iirc. The big problem with it is density.

The thing that limits top wood choices is the fact that you need to have a certain static stiffness to withstand the bridge torque, and only have a limited amount of energy in the string to produce sound with. The heavier the top is the less sound it's likely to make, and, as has been said: "Give 'em volume and they'll hear tone". For all of the 'usual suspect' soft woods it turns out that the lengthwise Young's modulus, a measure of how stiff the top will be at a given thickness, varies pretty much the same way with density. If you graph the two out, the points all tend to fall close to the same line. Since the actual stiffness of the top varies as the cube of the thickness, that means that usually you'll get a lighter top, and more sound, by using a wood with low density.

I have not tested many varieties of hardwoods, and can't say whether the same rule holds for them as well. I can say that for Indian rosewood, the wood I have the most data on, the lengthwise young's modulus is often no higher than that of some of the denser softwoods. I have IRW samples that have the same lengthwise stiffness values as redwood and Red spruce. This means that you'd have to leave an IRW top about as thick as a Red spruce one for it to hold up well, and it would be pretty heavy, since the density of IRW is much higher than that of Red spruce.

If I wanted to make a hardwood top, then, I'd be looking at the low density ones. Some mahogany and koa is pretty light, cedro would be a good bet, as would it's North American analog, butternut. A cedro/mahogany guitar could look interesting, and butternut can be stained to look a lot like walnut, so that would be another 'monochrome' alternative. For that matter, Peruvian walnut can be pretty low density. You might get lucky and find some really soft maple, or poplar, that would work. And let's not forget that balsa is technically a 'hardwood'. Sure, it dents even more easily than cedar, but think of the weight saving! There have been some interesting experiments with balsa violins of late.

I've seen where Douglas Fir, alpine hemlock, black fir, British Columbia Douglas-fir, Canadian Douglas-fir, coast Douglas-fir, Colorado Douglas-fir, cork-barked Douglas spruce, Douglas pine, Douglas spruce, gray Douglas, green Douglas, groene Douglas, hallarin, hayarin, hayarin Colorado, inland Douglas-fir, interior Douglas-fir, Montana fir, Oregon, Oregon Douglas, Oregon Douglas-fir, Oregon fir, Oregon pine, Oregon spruce, Pacific Coast Douglas-fir, Patton's hemlock, pin de Douglas, pin de i'Oregon, pin d'Oregon, pinabete, pinho de Douglas, pino de corcho, pino de Douglas, pino de Oregon, pino Oregon, pino real, Puget Sound pine, red fir, red pine, red spruce, Rocky Mountain Douglas-fir, Santiam quality fir, sapin de Douglas... has been used for sound boards.

Does anyone have an opinion on the use of this species?

d

Never heard of it.

Tas Blackwood would be fine and within the Acacia Melanaloxyn species you will find a wide variety of density and weights with the lighter stuff obviously being more suitable for tops.

It actually occurs all along the Eastern seaboard of Australia with Tasmanian and Victorian Blackwood being virtually indistinguishable.

The Blackwood that comes out of Queensland is as dense and heavy as Mulga, Gidgee, Myall and any of the other desert Acacias.

I'm using it at present for bridges.

Bob the Tasmanian

_________________

------------------------------------------------------
Bob Connor
Geelong, Australia

On the topic of using hardwoods for tops it may be posable to use a species of wood that would not normaly be suitable for tops if you find the right peice.
As all guitar makers know every single piece of wood is diferent even diferent boards from the same tree.
for example i have some very pretty strawberry and cream paduak that had a density and texture a little like mahogany and is very light in total contrast to standard paduak.
this wood had wonderfull stiffness ratio's both with the grain grain and cross grain and really rang like a bell.
i made an experamental guitar with this and the results were very pleasing.
the guitar has a beutyfull even response and and nice volume and clarity with out the loss of tone.
this is just an example that if you sometimes think outside the box you can get good results.
sometimes it wont work but unless you try you will never find out.
that said i would never think of using the standard denser paduak on a top as it is just too heavy but these boards worked out fine in this case.
i have since sold a few sets of back side and top sets to a few people who have been very happy with it.
in future i will look for this type of wood as i think it makes a nice novalty if nothing else.

the moral of the story if you experement you never know what you may find.

joel.