crazy questions

[blazemite]

ok ive got a few questions about some of our traditions when it comes to guitar making.

1,) why do we use soft woods for a soundboard? hardwood seems to be the wood of choice for some intsruments such as a marimba, where all of the vibrating plates are hardwood? im thinking you could get a thinner less braced board with hardwoods ?

2,) why are some of the denser neck timbers such as maples and rosewoods avoided for acoustic guitars? is it a sonic/structural/weight preference?

3,) why do we usually use hard woods for backs? most of the "traditional" flamenco guitars seem to be cypress all over, which is pretty light and alot softer than say ..rosewood ...

im sure you have perfectly good reasons for all of these, but i don't particularly have the funds to experement and find this stuff out myself .... any advice on these questions would be appreciated.

[liam_fnq]

Ok, I only build ukes but I'll give it a go.

1) A spruce marimba bar wouldn't last long.

2)neck would be very heavy.

3) different timbers will give a different sound.

points to consider:

It's not hard to find exceptions to the rules.

Certain design parameters/features are considered 'convention'. Much easier to sell a rosewood bodied, mahogany neck, spruce topped guitar cos that's what lotsa folk want.

[Bob Connor]

ok ive got a few questions about some of our traditions when it comes to guitar making.

1,) why do we use soft woods for a soundboard? hardwood seems to be the wood of choice for some intsruments such as a marimba, where all of the vibrating plates are hardwood? im thinking you could get a thinner less braced board with hardwoods ?

2,) why are some of the denser neck timbers such as maples and rosewoods avoided for acoustic guitars? is it a sonic/structural/weight preference?

3,) why do we usually use hard woods for backs? most of the "traditional" flamenco guitars seem to be cypress all over, which is pretty light and alot softer than say ..rosewood ...

im sure you have perfectly good reasons for all of these, but i don't particularly have the funds to experement and find this stuff out myself .... any advice on these questions would be appreciated.

1. Because they are light in weight. Think strength to weight ratio.

2. Rosewoods are too heavy generally ( they have been used though) but Maple has been used on countless millions of Strat and Tele necks (not to mention copies. It's also used on acoustic necks.

3. Hardwoods will assist in projecting and colouring the sound that is emanating from a spruce or cedar top. and will also provide some sustaining characteristics. Flamenco guitars are very percussive instruments with quick attack and decay to the note. Probably not what you want for a steel string guitar or even a classical.

Regards

[Mark McLean]

You do see some acoustics with hardwood soundboards, eg all mahogany Martin 15 and 17 series, Guild M25 (Nick Drake style), and there are lots of stunning looking all koa guitars around. Also, check out the Taylor W series (all walnut). You are right that the tops on those can be made thinner (at least 0.5mm thinner than you would go for spruce, and about 1mm thinner than for a cedar top). Like Bob said, hardwood is heavier and if you made it too thick it would be very unresponsive. My son has an all-mahogany Martin 000-15. It has quite a different sound from a spruce top - more compressed and "woody", less bright, less sustain. But a great sounding guitar.
Mark

[jeffhigh]

It's a commonly held belief that hardwoods are stiffer than softwoods, but spruce is a pretty remarkable wood.
It is both lighter in weight and stiffer (modulus of elasticity) than mahogany (average figures)
Whilst some of the denser hardwoods are stiffer, when you take into account the cube rule for bending, you probably can't reduce their thickness sufficiently to compensate for the extra density.

I am not saying you can't produce a good guitar with a hardwood top, just that you may not have much scope for reducing thickness, and it will most likely produce a different sound.

Mahogany can be one of the lighter hardwoods (though there is a lot of variation) so it is not surprising that it works as a soundboard.

[Allen]

Some if this has to be put down to tradition as well.

Spanish style guitars were made from local woods (cypress) and the market settled itself into cypress guitars being sold to the "Peasant" class that played Flamenco, and expensive models with imported hardwood backs and sides that could only be purchased by those with a lot more money gravitated to the more "Serious" styles of music of the time.

[joolstacho]

I just finished an all Blackwood body Jumbo, with a Blackwood top. (and Maple neck!). I did thin the top more than I would Spruce and did a lot of work on the bracing scalloping. It has a distinctively different tone, very nice, sort of twangy/glassy without being harsh in any way.
That difference in tonal quality makes a nice change from the USTG. It'll be interesting to see how it ages. (Better than it's builder I hope!)
-Jools