I hope it can be seen on the photograph. This is a berg Larssen metal mouthpiece 100 2 SMS. There is some material removed from the middle of the ceiling (I don't know the right name of that, but it can be seen on the photo). Is this smal trough original? And if not what is the purpose of it. Should I leave it that way of fill it with epoxy?

I hope it can be seen on the photograph. This is a berg Larssen metal mouthpiece 100 2 SMS. There is some material removed from the middle of the ceiling (I don't know the right name of that, but it can be seen on the photo). Is this smal trough original? And if not what is the purpose of it. Should I leave it that way of fill it with epoxy?


I would leave it alone as I doubt that small amount of metal removed would have an effect on the tone, nor would filling it change it. 

That place is usually called the "roof".

Paul C.