Sound samples or it didn't happen!
You'd make a lousy witness. :music:
BTW, I was wrong about my 1st-gen Filco keyboards. This is the actual situation:
Tenkeyless (x2), blue switches - very slight ping, immediately deadened.
Tenkeyless (x2), brown switches - very slight ping, immediately deadened.
Tenkeyless (x1, black otaku), brown switches - no ping.
Tenkeyless (x2), black switches - noticeable ping, quickly deadened.
As you can see, I really like Filco keyboards! Until this week I never thought about pinging or ringing as an issue. I don't think it matters the slightest bit, unless it's loud and causes the metal plate to resonate. (The so-called Tuning Fork Effect.)
Anyhow, I shouldn't have used the word "ping" to describe the "sustained metallic ringing" of the keyboards I returned to Amazon. That was confusing.