Some have said that 'some barrels just don't ring, but are solid'. I used to think they were right. Lately, I have experienced the relatively short ring (not thud) and thought that's just the way they are, but are solid from visual exam. Wrong! The ribs were working loose but not detectable, visually yet. After refinishing, they showed. Then, I re-layed the ribs and the barrels ring like church bells. So, I don't buy the 'some just don't ring, but are solid' line. Something's going on in there, even if it won't show for years.
