72-6948 Tenma, Digital Audio Speaker Impedance Tester | Farnell Italy
1107 IM Audio Impedance Tester 0-20kΩ | Hoyt Meter
Archimago's Musings: MEASUREMENTS: Speaker Impedance - Part 1; measurement box, dummy loads and single speakers...
How To Tell The Impedance of A Speaker - A Guide For Everyone
TOA ZM-104A Impedance Meter, Measures Impedance of Speaker Lines Up to 100k Ohms, Zero Adjustment for Accuracy On All Ranges, Easy to Read Meter Calibrates Directly in Ohms - Amazon.com
Build a Loudspeaker Impedance Meter w/ Arduino & iPhone w/ SGenerator - YouTube