Making the Top of a Gasparo da Salo Viola

Today in the shop, Gregg is working on making a top for a new viola based on a model by the Brescian maker Gasparo da Solo:

It is interesting to note that one characteristic of the Brescian makers is that they beveled the inside of the f-holes on their instruments, as Gregg is doing here:

Anyone want to venture a guess as to what this bevel does to the Helmholtz frequency?