Solved! Church Speakers - Can I test voltage on speaker wire?

[serihon]

Hey everyone,

I have taken over the sound system maintenance for our church and last year we replaced our old mixer with a powered mixer. We currently have two speakers that work with the system but over the year I found two speakers that weren't working and I am not sure if they ever worked. There are a lot of unknowns about the current setup and system as there wasn't much documentation on the wiring layout, etc.

The two speakers that weren't producing sound appear to be dead as I pulled them from their location, in an air conditioning vent, and testing for resistance and got nothing from the two ports on them. Based on some research they shouldn't have ever been used with our old mixer and amp combo or the new powered mixer since they couldn't handle the voltage.

What I would like to do now is figure out whether the wiring running to the two bad speakers is on the same loop as the speakers that are currently working or if they are a second set of wires that come to the sound board and aren't currently used. Would it be possible (and safe) to connect a multi-meter to the two wires that were connected to the speakers, while the soundboard is on and the cord that I "think" is sending power and sound to them is connected, and see if a) the line is the one I think it is or if it is on the same loop as the current speakers and b) whether it is getting power/going to the board at all.

What are your thoughts?

Here is some additional information.

Speakers that are dead: 2x Bose Model 100 speakers
Speakers that are working: 2x Woodworx WX6A speakers
Mixer: Peavey XR1220
Connectors from the sound board to the speakers: Neutrik
Ability to trace wiring: Not really, it was ran by someone else and goes into the walls at various points.

Please let me know if you have any questions or suggestions. Thanks!

 

[americanaudiophile]

There are different ways to check those wires.
One is to connect a voltmeter across the speaker wires. Play test tone so you will get a constant reading. VOM set to AC.
Another is to put a resistor across the speaker wires with the other speakers disconnected. You would be able to read the resistor plus the wire resistance at the mixer end.
Another is to connect any other speaker (could be just tiny raw speaker or one of the working ones) to the speaker wires.

 

[serihon]

americanaudiophile, thanks for your response.

I would probably try option 1. It is good to know that a tone needs to be going over the system in order to get any reading, thanks for that.

A congregation member did purchase a speaker from Goodwill or Dick's Pawn Shop to test with but the speaker is only rated for 100 watts and the powered mixer puts out 600 or so, won't it fry the speaker?

 

[americanaudiophile]

Start with the mixer output volume all the way down and turn it up slowly. You should be able to hear the test speaker with about 1-2 watts especially if someone is right next to it.