wrote in message
oups.com...
Every year or two CU tests popular speakers, and while most speakers
claim to be 8 ohms, CU finds most to measure 4 ohms. Although CU's
opinions should to be taken with a grain of salt, measurements are
measurments, and not opinions.

I don't read CU so I can't comment on their alleged "4 ohm" claim.
However, the key word is "nominal" that should precede "8 ohms".
Another point is minimum impedance. Nominally 8 ohms speakers can go
as low as 4 ohms at some frequencies, putting a bit of a strain on
cheap amplifiers that can't deliver the required current. Ideally,
you need the whole impedance vs. frequency graph, complete with phase
angle.
Cheers.
Roger