Why are guitars constructed without soundposts ?

[essexbasscat]

One for the luthiers.

While reading around the topic of Cellos and Violins, I came across the observation that altering the position of the soundpost can influence the sound of the instrument.
That led me to wonder about the construction of the acoustic guitar and bass. I've yet to come across a guitar with a soundpost (typical of the Cello and Violin).

On the face of it, a soundpost from top to bottom could potentially strengthen the wooden box of the acoustic guitar or bass and offer a means of vibration transmission.

Does anyone know if it's been tried ? what the issues were ? Any results ?

Thanks for any thoughts on the topic

[xilddx]

I have a Breedlove acoustic which has something along these lines called a bridge truss. But it's more for stability than tone shaping.

http://www.acousticguitarforum.com/forums/showthread.php?t=210916

[janmaat]

Hey wait, this is on guitars not basses!

[RhysP]

A lot of Gretsch hollow body guitars are built with sound posts.

The ones that don't have sound posts have trestle bracing and, as you'd expect, there's a lot of discussion about which sounds best....

Edited January 5, 2012 by RhysP

[LemonCello]

Sound posts in classical stringed instruments are used to compensate for the pressure bearing down on the convex belly of the two footed bridge. They also serve to internally join the belly to the back allowing circulation of air within the instrument when the strings are bowed. I had one fall over on an old Cello a few years ago and the result was a very muddy sounding instrument. They are also a pigs orphan to get back into position and you need a special tool. Interestingly, just by moving the sound post a fraction can alter the sound (timbre) of the instrument enormously. Something best left to experienced luthiers. I've never heard of them being used in guitars?

LC

[krysh]

I have a Guild X-170T with a soundpost. These are usually mounted under the bridge for
a) better structural integrity
and more important
b) to reduce feedback resulting from vibrations of the top and bottom.
you will often find soundposts in electrical archtop guitars.

Edited January 5, 2012 by the_krysh

[leftybassman392]

...and then of course there's the Gibson 335 and it's sisters, that have a solid block of maple running the entire length of the body, with a width of (I think) around 4 inches. That has a gorgeous tone.

Edited January 5, 2012 by leftybassman392

[BigRedX]

One of the functions of the soundpost on the violin family of instruments is to transfer the vibrations of the top to the back of the instrument.

Since on a guitar the back of the instrument is normally in contact with the player's body and therefore being damped, it doesn't make much sense to connect the from and back surfaces in this way.

[geoffbyrne]

[quote name='leftybassman392' timestamp='1325767352' post='1487267']
...and then of course there's the Gibson 335 and it's sisters, that have a solid block of maple running the entire length of the body, with a width of (I think) around 4 inches. That has a gorgeous tone.
[/quote]

......maybe not an acoustic one, though.......

G.