I will try to answer your question. F style Mandos have a scroll on the top side and usually a scroll on the headstock pointing the other direction. There are 2 basic types. Those with 2 F shaped sound holes on the each side of the strings. The other is an oval shaped hole the is right under the strings between the bridge and the fret board. The F holed one is referred to as a F5 model and the oval hole is revered to as an F4 model. This is following the Early models numbers of these models that Gibson established in the 1910s and 20s. A types are usually tear drop shaped and come in either F sound hold or oval sound hold types. These tend to be a bit cheeper for the same quality. F sound hole mandolins tend to send the sound out in a more direct path, while the oval will spead the sound out more. The F5 is usually considered the bluegrass instrument, but some like Tim O'Brien use an A very effectively. Flat tops are just that flat. Carved tops are are not flat and are carved with hills and valleys, excuse the analogy, often from a solid piece of wood. Flat tops are described as have a more simple clear tone and carved tops more complex. This is not always true, just a generalization. I hope this helps.
Tony
Tony Huber
2008 Gibson RSDMM #19
2008 Ellis F5 #119
2008 Old Wave Dola
2011 Mowry GOM
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