Would a split bridge design work?

[brianli408]

Well some may recognize me that I have raised some question on building my first guitar kit. The guitar bridge is the only thing that I have to shape it down into a bridge from a blank. So I make a lot of thoughts, including bridge position, size, saddle and pins position, mass, etc...
However I had a really stupid idea that splitting the bridge into half–just like how the soundbard does. Does this make the guitar bass and treble to vibrate independently, and get a more detailed tone

[jimmorgan]

Some Alvarez/Yairi guitars featured/feature a split saddle. I've never noticed that much a difference in the few I've played.

[printer2]

Some split the saddle and angle them differently rather than shape the saddle in order to compensate some strings. The bridge is such a solid mass what happens on one side of the saddle will vibrate the bridge as much whether the saddle is split or not.

[LeightonBankes]

generally speaking, the bridge is considered a brace, strengthening that area of the soundboard. Cutting it in half would be akin to cutting one of your braces in half. Will it "separate the bass and treble? No, sound is a lot more complicated than that. Good news, you can skip the bridge pins though and make a pin-less bridge (don't have to buy pins, fit them, wear them out or lose them or break them)

[Alan Carruth]

As has been said, the bridge is a brace across the top: the heaviest of all the braces and one of the stiffest. Splitting the bridge in the middle, between the 3d and 4th strings, reduces the crosswise stiffness of the top. This has a similar effect to 'scalloping' the braces, allowing the center of the top to flex more, and pumping more air in the low frequency range.

This is a trick that has been used a number of times that I have seen, either before or after the guitar was strung up. The Sullivan-Elliot harp guitar that John Doan plays has a split bridge. In that case the bridge carries all 20 strings, and runs most of the way across the top. Jeff Elliot, in his article about it in American Lutherie, mentioned that the sound was not satisfactory until they cut partway through the bridge. I incorporated that from the outset when I made one based partly on that guitar a few years ago.

[printer2]

Oops, read your post wrong, did not comprehend someone cutting the bridge in half.

[Otterhound]

Any loss of mass or support created by altering the bridge should be able to be compensated/enhanced via the bridge plate .
The bridge is the only external top brace on the conventional acoustic guitar .
There is no rule that states that the bracing action of a bridge must be applied outside of the top .
Experimentation is learning . Innovation is priceless .
Keep learning and questioning .

[Badcrumble]

Two separate bridges will also introduce two sources of vibration on your top. I can't really comment on the effect of this, but keep in mind that the vibrations/waves of each source will interfere with each other.

[Alan Carruth]

badcrumble wrote:
"Two separate bridges will also introduce two sources of vibration on your top."

In theory, perhaps. If I understand how this stuff works it would only be an issue at high frequencies, where the wave length of bending waves in the top is shorter than the distance between the centers of the two bridges. That's up around 1000 Hz, more or less. This is the 'resonance continuum' of the guitar, where there are so many resonances spaced so closely together that it's difficult to ascribe any one peak in the output to one part of the guitar. In this range very small differences start to matter, and it may well be impossible to control things tightly enough to get guitars to sound 'the same' even when they are materially and structurally 'identical'. Splitting the bridge will make a difference in that range; everything does. Characterizing the difference, and deciding whether it's 'good' or bad', or even whether it's due to the bridge or something else, might be difficult.

OTOH, we know that splitting the bridge will alter the crosswise stiffness of the top (al else equal), and change the low frequency modes: in particular, the 'monopole', and the 'cross tripole' if there is one. These are easy to identify, and help establish the basic character of the timbre of the guitar.