Effect of bridge plate on sound ?

[wolfpapa]

I have a JF30-12 that is almost 20 years old, the top has developed a slight belly under the bridge, and the bridge is slightly lifting. It sounds wonderful, plays well, and stays in tune. If I were to have a bridge plate installed, would it change the sound in a negative way? I'm guessing that it could stiffen the top enough to dampen the top's vibrations. I love the sound, and don't want to alter it.
Is it possible the the top has reached some equilibrium and won't continue the bellying and lifting? Or is this something that will worsen?

 

[Heath]

Given physics I suspect it will continue, but you might have years before you need to address it further.

 

[Br1ck]

Bridge lifting should be dealt with. As to predicting wood, well you really can't. I've seen where gluing in a new bridgeplate and bridge with the top clamped flat can help. but if your problem is slight, and you have great action, why bother? Get your bridge reglued and without mentioning anything, have your luthier check out the guitar.

Doing practically anything to a guitar can change it, or not. Weather you'll like the change is another matter. I've shown my 65 Epi Texan to three respected luthiers wondering about the adj. saddle and large ply bridgeplate. The question was always, do you like the guitar? The answer was always yes. Don't mess with a good thing. When I bought the Texan, there were four like vintage J 45s in the shop. Two had the adj bridge removed. They were still dogs. The others were good to very good guitars. No reason to change them.

 

[GardMan]

If I were to have a bridge plate installed...

I am confused a bit by this... your JF30-12 HAS a bridge plate. The "bridge plate" is a thin wood piece attached to the underside of the soundboard (top) under the bridge footprint, to help reinforce that area of the top. The size and composition (type/density of wood) of the bridge plate most definitely can affect the tone...

Do you mean a larger bridge plate? A "plate mate" (a metal piece that reinforces and protects the pin holes in the bridge plate)? or a "bridge doctor" (a truss installed between the bridge/bridge plate and the tail block that can be used to reduce bellying of the top)?

 

[davismanLV]

There are mixed reviews but mostly the people I know and respect have used a JLD Bridge Doctor to fix bellying and restore a more original geometry to their guitars. It's a truss rod system that works very well for what you're describing. Watch this video and see if you think it would help the situation you're describing.



p.s. - your guitar already has a bridge plate inside between the braces that supports the bridge and pins. Unless something is wrong with it, that isn't your problem.

 

[wolfpapa]

I am confused a bit by this... your JF30-12 HAS a bridge plate. The "bridge plate" is a thin wood piece attached to the underside of the soundboard (top) under the bridge footprint, to help reinforce that area of the top. The size and composition (type/density of wood) of the bridge plate most definitely can affect the tone...

Do you mean a larger bridge plate? A "plate mate" (a metal piece that reinforces and protects the pin holes in the bridge plate)? or a "bridge doctor" (a truss installed between the bridge/bridge plate and the tail block that can be used to reduce bellying of the top)?

Hello - Thanks for the information, I didn't know that there was a bridge plate, but now thinking about it, it makes sense

Larger bridge plate or metal ? Probably whatever is the standard repair, if there is such a thing.

 

[wolfpapa]

There are mixed reviews but mostly the people I know and respect have used a JLD Bridge Doctor to fix bellying and restore a more original geometry to their guitars. It's a truss rod system that works very well for what you're describing. Watch this video and see if you think it would help the situation you're describing.



p.s. - your guitar already has a bridge plate inside between the braces that supports the bridge and pins. Unless something is wrong with it, that isn't your problem.

Thanks, that video looks like a Bridge Doctor might be the solution.

 

[mclkar54]

i have the exact same bridge doctor installed installed in a70,s epi texan.its been in there for 9 months,no undesirable effects at all.

 

[gjmalcyon]

Many guitars have a belly and guitars need a belly for tone.

See post #6, here:

In the process of grabbing this f-212, thoughts?

Hey gang, Currently have my eyes set on this '64 F-212 (https://reverb.com/item/38388087-vintage-1964-guild-f-212-12-string-acoustic-guitar), allegedly with a neck reset and the associated fret level/crown done by Retrofret, so I feel pretty confident in it's condition. The seller says it has a...

letstalkguild.com

My JF4-12 (17" jumbo mahogany archback) has a moderate belly that has not changed in the nearly 9 years I've had her. Just watch for changes.

Guilds are also known for bridges that lift, at least at the bottom of the bridge thanks to the method Guild used to finish guitars, then attach bridges. Use a business card or index card and see how far you can insert it. Make a mark and check it again in a couple of months. It it does not change, don't worry about it.

 

[wolfpapa]

Many guitars have a belly and guitars need a belly for tone.

See post #6, here:

In the process of grabbing this f-212, thoughts?

Hey gang, Currently have my eyes set on this '64 F-212 (https://reverb.com/item/38388087-vintage-1964-guild-f-212-12-string-acoustic-guitar), allegedly with a neck reset and the associated fret level/crown done by Retrofret, so I feel pretty confident in it's condition. The seller says it has a...

letstalkguild.com

My JF4-12 (17" jumbo mahogany archback) has a moderate belly that has not changed in the nearly 9 years I've had her. Just watch for changes.

Guilds are also known for bridges that lift, at least at the bottom of the bridge thanks to the method Guild used to finish guitars, then attach bridges. Use a business card or index card and see how far you can insert it. Make a mark and check it again in a couple of months. It it does not change, don't worry about it.

Thanks

 

[Tom O]

My J-50 Gibson always had a belly. Put the bridge doctor on my 1974 FG-260 to get the action back down. With some magic (steam?) from my luthier it didn't need a reset and action is now as low as a Guild.

 

[12stringer]

I had a slight lift on my JF30-12 bridge. I could not slide a business card under but a paper receipt went under about 1/8 of an inch along the bottom. Because Guild glued their bridges on top of a very thin line of finish at the bottom of the bridge, they are prone to a lift only where the finish is.
My guitar tech told me to leave it be as long as I can not slide in a paper any further over time.
Also, make sure your room is around 40 percent humidity. To wet can cause belly and to dry the opposite.
My guitar was a bit over humidified so when I removed the kyser lifeguard humidifier after a few days the belly went down a bit and the bridge became tighter to the top.

Hope this helps.

And if I am wrong about any info, please members jump in and correct.

Happy picking!