Sometimes a client will visit us and want to know what they are doing wrong, because their bowl won't sing very well. The answer is... they are doing nothing wrong... it is a dud bowl. It might be great as a bell, but it just won't sing.
Here is a sample of one bowl that wont' sing for more than a few seconds.
There are some dud bowls out there. We don't sell them, we play every bowl before shipping to make sure you are going to love the sound it creates.