This is an area of interest for me too. A close friend's church had lots of PA gear stolen. I'll be doing the installation and don't want to be attaching a new power amp before testing the long speaker cables. Strangely another friend's church needs work on their 70v system with 8 speakers in the ceiling. I've been running sound for churches for decades, not doing installations. So I need to purchase something reliable.
There are relatively inexpensive devices available that will test AC impedance for audio applications--not DC resistance.
https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=speaker+impedance+meter&_sacat=0&LH_TitleDesc=0&_osacat=0&_odkw=impedance+meter
The more expensive ones will test impedance at various frequencies. Some will also calculate "watts" for those testing a larger number of ceiling speakers running on a commercial 70v system, etc.
http://www.gold-line.com/zm1.htm
There is a software based app that has lots of bells and whistles. The package is very pricey due to the required $500 audio interface plus the app
https://www.studiosixdigital.com/audiotools-modules-2/speaker-test-modules/impedance-meter--sweep.ht...
The inexpensive Chinese impedance meters only test at 1khz.
https://www.ebay.com/itm/Digital-Audio-Impedance-Tester-LCD-Display-Speakers-System-Resistance-Ohmme...
The choice of 1khz seems strange to me. My understanding is that the standard frequency for testing woofer impedance is 400hz.
You can see why 400hz is more suitable for testing speakers since impedance varies greatly according to frequency!
https://www.studiosixdigital.com/_Media/impsw5.png
There are relatively inexpensive devices available that will test AC impedance for audio applications--not DC resistance.
https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=speaker+impedance+meter&_sacat=0&LH_TitleDesc=0&_osacat=0&_odkw=impedance+meter
The more expensive ones will test impedance at various frequencies. Some will also calculate "watts" for those testing a larger number of ceiling speakers running on a commercial 70v system, etc.
http://www.gold-line.com/zm1.htm
There is a software based app that has lots of bells and whistles. The package is very pricey due to the required $500 audio interface plus the app
https://www.studiosixdigital.com/audiotools-modules-2/speaker-test-modules/impedance-meter--sweep.ht...
The inexpensive Chinese impedance meters only test at 1khz.
https://www.ebay.com/itm/Digital-Audio-Impedance-Tester-LCD-Display-Speakers-System-Resistance-Ohmme...
The choice of 1khz seems strange to me. My understanding is that the standard frequency for testing woofer impedance is 400hz.
You can see why 400hz is more suitable for testing speakers since impedance varies greatly according to frequency!
https://www.studiosixdigital.com/_Media/impsw5.png