Is it possible to replace an acoustic guitar bridge?

[TheGkbrk]

I got a Washburn WD10SCE that I haven't played for a while. The strings got went into the bridge's wood. Is there any chance I can change the whole bridge??
This is how it looks:
https://ibb.co/nL9vRv
https://ibb.co/ewDpmv

[YamaYairi]

That is normal. Do not replace it. There is often a groove purposely put in the bridge for the strings.

[DCCougar]

Originally Posted by TheGkbrk

Is there any chance I can change the whole bridge??

Certainly you could, but I'm not sure you'd need to. Do the strings stay in the peg holes when you're tuned to pitch? I don't imagine the sound/tone is affected. Why replace it?

When a saddle has been shaved too much (to improve the action), one might postpone a neck reset by cutting slots or ramps in the bridge pin holes in order to improve the break angle (and hence, improves the amount of vibe going to the soundboard). Ramped on the right....

[TheGkbrk]

So there is nothing wrong with bridge wood being pushed inside by strings?

[redir]

It doesn't look like a problem to me as long as the strings stay firm in place. But to answer your question yes you can replace a bridge, I get at least one or two of those type jobs a year. Much more though instead of a full replacement would be to remove the bridge and reglue it and repair the bridge if necessary.

[Sperry]

My 1996 Guild D4 bridge is even more deeply slotted.

[TheGkbrk]

Ooh that looks more deep for sure. Thanks for all answers, I will keep my bridge as it is.

[Neil K Walk]

Some people actually pay to have that done. It increases the break angle of the strings and applies more force on to the saddle and increasing transmission of the string vibrations. The only thing I'd be concerned about would be if anything more chips away on either side of the string. I would actually have a luthier refine the indentations, but it's certainly not a big problem so much as you're careful not to try to push the bridge pins in too far when restringing.

[Alan Carruth]

DCCougar wrote:
"When a saddle has been shaved too much (to improve the action), one might postpone a neck reset by cutting slots or ramps in the bridge pin holes in order to improve the break angle (and hence, improves the amount of vibe going to the soundboard)."

This is a common misconception. Actually, so long as there is a enough break angle so that the strings stay in contact and don't move sideways throughout the entire vibration cycle all of the force of the string should be transmitted to the top. More break angle than that won't help.

I did an experiment several years ago where I used a mechanical plucker that drove the strings with a known force and made them vibrate only vertically with respect to the soundboard. I recorded the resulting single string plucks and put them together to make 'synthetic strums' for different cases. I used a Classical guitar, and modified the bridge so that I could tie the strings off to get two different break angles, six degrees and 25 degrees, using the same saddle height. I also recorded sounds using a tall saddle that moved the strings to 18mm off the top, instead of the original 11mm. The 'strums' were played back in random pairs through headphones to see if people could hear any difference.

Basically, in the two cases with the same saddle height but different break angles, they could not tell them apart. When the saddle was raised there was a clear difference.

I also evaluated the sounds objectively, looking at things like rise and fall time, maximum amplitude, and the frequency mix. There was no difference in the overall power output with any of the setup changes, but the spectrum of the sound did change when the strings were higher off the top. That's what people heard.

Again, my setup ensured that the strings always started out moving 'vertically'. If there had been any horizontal component to the string motion they might have rolled sideways on the saddle top, particularly in the low break setup, and that would probably have changed the sound. In normal playing there is some horizontal string motion, so a break angle steeper than my 'low' of six degrees would be necessary to cut that rolling out. It's hard to know how much that would be, but I'm pretty sure that anything greater than, say, 15-20 degrees would be 'enough'. A lot probably depends on the exact structure of the bridge.

This was done using nylon strings, but the physics of the situation is not that much different for steel. I'd be happy to help anybody who wants to try replicating my experiment using steel strings.

[yellowesty]

An interesting and useful post, Alan. (As usual.) Thanks.

[redir]

Alan's experimental work has changed more then one of my common guitar building philosophies that I've held since the early 90's. The process known as science is a wonderful thing and I'm always grateful to the ones who take the time out to actually run the experiments and publish the results.

Cheers. :beer: