[ljguitar]

Originally Posted by bosrocker51

I know this is an older thread, but I have to comment. A well made flat top guitar should never have the top deform, bridge tilt forward or any such thing if it is well made, properly braced and it is not abused with strings that greatly exceed it's capability to retain.

OK bos…
This just is not true.

All well made guitars - and in particular the ones which are braced a bit lighter to be responsive - will lift behind the bridge; especially behind the bass side. It's normal and natural, and not dangerous nor a sign of poor build or quality. It's not a defect, but a characteristic of being a guitar.

This 'deformation' will also cause the bridge to tilt ever so slightly forward requiring a slight intonation adjustment. It's inevitable. Builders even lean into it by building a slight backward tilt to the saddle so as the guitar ages, the saddle straightens.

While some tops are cambered for strength, even they will lift a bit more and even a really well built true flat top Olson guitar (I have one that is 18 ½ yrs old) will lift behind the bass side of the bridge to look like the top was built with a radius. I've had a discussion with James Olson about this...and about mine in particular. He assured me it's normal, and to be expected.

I do realize building a guitar which is responsive is a game of compromises - not reducing the quality but balancing quick attack versus response times, and highlighting projection etc.

But if you get out an 18'' straight edge and lay it across the top of a well built acoustic guitar with a solid top (right behind the bridge area), you will find that there is bump/bulge/lift there.

Could it be prevented?
Sure, but I think the guitar would have to be braced like a HumVee. That would certainly reduce the responsiveness in some way to counteract the characteristic bump. Personally I don't want several ounces of trussing inside my guitar hanging down to counter this 'imaginary' enemy.

If the bracing in front of the soundhole gives way, or a major brace under the bridge area cracks, that can result in a dangerous condition, but that will show itself by the inside of the soundhole dipping down.

The dipping from injury is totally different than a natural bump behind the bridge caused either by radiused building or string tension.