Split frequencies

[KreherGuitars]

What would cause a frequency to split? My air is at 114. And my top was at 228. I started sanding some lattice in my lower bout area and it split and it’s now at 205 and 230hz nothing happens with chladni at 205 but I get the monopole at 235hz. Science is weird.

[johnparchem]

I think the back shows as a monopole. I think when the top was stiff the back and the top were on top of each other. I have no idea why you do not see a pattern at 205, when you see a resonant peak there.