I just use my ears. The degradation from a low battery is hard to miss. This being said, I once changed the battery while at my tech's for other work and for kicks, he checked the voltage at the time. It was just above 6 and the buffer was working still. This was, though, a CAE buffer, not one of Mike's (I've since swapped out the CAE for a Wald).
When we Go to Heaven, will Jer ask whether we were the perfect Jerry ... or whether we were the perfect us?
What does Jerry tone mean to you? Copying Jerry slavishly? Honoring Jer's music no particular way but our own?
We're each of us unique. And also the same. Can we open our hearts and minds to both?