[Elecraft] Poor CW note more testing and a question (rather long-ish...)

[Andy Durbin]

"I got the report that my CW sounds just fine until the amp is in line. Then it is described as "some kind of artifact... like a bell sound... like a delay." This is consistent with the other report I had been getting of a "ringing, bell-like" note to my CW. This is most apparent at 30 wpm, as I would be running in a contest."

I'm probably well out of my depth here but could this be caused by incorrectly configured ALC feedback from the KPA500 to the rig?   That should be easy to test by simply disconnecting the AUX cables and running the CW test again.

73,
Andy, k3wyc