In message , Phil Allison
writes

"Ian Jackson"

Is there going to be a prize for suggesting the most obscure (but
effective) way of determining the phasing?


** I got one:

Insert a pin through a hole in the earphone grille and let it rest loosely
the diaphragm.

Use the AA cell test.

One polarity will evict the pin.

I reckon that one's certainly for the shortlist for the prize.

Of course, the principle is not new. You can test loudspeakers with a
battery, and watch which way the cone kicks. That would be difficult to
do with headphones, and 'kicking the pin out' overcomes this problem.
--
Ian