Flat vs Arch

[Charley wild]

What are the differences between say, a Gibson A ("O" type) and a Martin? I've never played any flat top or back (or both) type mandolin except a flattop bowl back once and it was so long ago I've forgotten what it sounded like. How important are the different shapes to the sound of a mandolin? And why?
Forgive me if this has come up before. I'm a new oldby.

[Charley wild]

Sorry I asked!

[Bill Snyder]

Charley, why are you sorry you asked? Sometimes it takes a while for people to respond.

[Eric F.]

The carved top and back Gibson ought to project more. The Martins can be very nice mandolins with a sweet sound, though in my experience they tend to be a bit quiet. Fine for playing alone or with a guitarist, not so much with a banjo. There's a recent thread about someone buying one off eBay you could look at. The Martins have a cant, or bent, top rather than a (more or less) completely flat top such as the Big Muddy or Flatiron pancakes have. In general, flat tops are often described as having a slightly more "boxy," "boomy" or "guitar-like" sound. Again, a generalization, but they usually have less projection, less ability to "cut" through the sound of other instruments. I like them, and have a Flatiron 2M sitting right by me at the moment. It's a very fun mandolin to play on a slow day in my office or out on the porch. It has a very bright, sweet tone to it, less rich than my carved top oval but quite nice in its own way.

[Jim Garber]

just an addendum to Eric's excellent discourse: the vast majority of flat mandolins actually do not have completely flat tops. They have an induced arch. You can see if when you try to fit a bridge to them. There has to be an arch otherwise the top would sink due to the downward pressure.

[Charley wild]

Thanks, Eric and Jim. How about the flat back? Didn't a model of the old Gibson A's have a flat back at one time? I read somewhere that on a guitar the back was of little consequence to a degree. The writer was exaggerating I'm sure but he wrote that you could put a masonite back on a D28 and it wouldn't make much difference if the top was braced right, voiced, etc.
I'm not looking to buy one or the other at this time, i.e. arched or flat, I'm just curious
Thanks

[8ch(pl)]

I think more modern flat tops project more. X Bracing etc. My Mid Missouri has lots of volume. I have only played one Flat top Martin and can't say how well it projected because I didn't hear it being played. One of the nicest Flat tops I have heard is a Gibson Alrite that had been converted to X Bracing. The top had separated from the 2 longitudinal braces and was rippled a bit. The luthier was able to save the top and flatten it out across the new braces. Alrites were not braced the same as Army Navy Flat tops.