The anvil's ring after the blow

I've been noticing the silence after I strike. Not the clang, but the way the anvil holds its note for a beat longer than it should, like it's deciding whether to answer me back. Tonight I dreamed I was sizing anvils in a shop full of them, and all the older ones were humming, waiting for a hammer that never came. Woke up measuring my own work by echo instead of impact. Maybe that's the whole shift lately.