[Elecraft] Why is my K3 off frequency?

[Andy Durbin]

"Calibration aside, stations checking into nets should always zero-beat the Net Control Station regardless of where he is on the dial and regardless of the net's published frequency."

O.k. I'll bite.   I started in amateur radio long enough ago to know how to use a BFO and to know how to zero beat an AM or CW signal.  How does one zero beat a suppressed carrier single sideband phone signal?  I just tune until the voice sounds like I think the voice should sound like.  It is very subjective and I certainly can't tune to less than 12 Hz error.

What technique are others using that enables them to "zero beat" SSB phone to better than 12 Hz accuracy?  I seldom use phone but I'd like to have this technique in my bag of tricks.

73,
Andy, k3wyc