Impedance meter

The industry standard is a TOA ZM104. It is a 1,000 hertz fixed frequency unit used for testing installed commercial sound systems. It has made virtually all other field type units obsolete.

Sennheiser was the previous go to model.

Before that General Radio bridges.

Most folks who want more data just use a gizmo like the "Woofer Tester" with a PC.

I suspect if you look you can find software that does it with the built in PC audio inputs and outputs and a resistor.
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Paid Member
2004-03-24 5:16 am
SF Bay Area