If they aren't sitting on the large diode speaker upgrade kit -- it would be worth while, time & finances permitting to purchase & install the diode kit from Wilson.

Also, if they are several years old, it would be a prime opportunity to remove the resistors on the rear and test with an volt-ohm meter. Wilson doesn't tell you this in any manual - it's a 'learned' experience -- when Wilson comes out for a demo, regardless how old the speakers are, they test the resistance on the resistors.

From Wilson -- "Resistors are in the crossover circuit in series configuration (parallel pair). A zero-ohm impedance is a dead short so the resistors would act like a piece of wire. What they wouldn’t do is set the proper level that the load does. New resistors should have greatly improved the sound."

A Sabrina has resistor values of 3.95ohm for the tweeters and 2.1ohm for the midrange.

Therefore, if you remove the resistors & take a VM across both leads, say of the tweeter (3.95 ohms) the VM should read 1.975 ohms (parallel value) and likewise half value for the mids. If the VM reads 3.95 ohms (for tweeter) & 2.1 ohms (for midrange, Parallel Value), they are good & can be reused -- a zero reading represents an open.

As a general preventive maintenance routine, I test my resistors approximately twice a year. I've replaced a few -- one speaker may be fine; whereas the other speaker has a one or several resistors showing opens, which are replaced.

If both speaker resistors are fine, I just reinstall & march on.

BTW, resistor "opens" have nothing to do with loudness of play. They just fail.

Bob

^ Great information. Thank you Bob.