Can You Physically See If You Have a Blown Speaker?

[Old Garage-Bander]

Plug a 1/4" cable in your cab, and touch a 9v battery to it. The bad speaker will suck in, or not move at all...sometimes.

You had me at "suck".
The voice, if it moves, will move out or back depending on which way you connect the battery.
If it doesn't move then the speaker just sucks.

 

[JeezyMcNuggles]

You had me at "suck".
The voice, if it moves, will move out or back depending on which way you connect the battery.
If it doesn't move then the speaker just sucks.
View attachment 4912486

I damage a speaker once. A tinsel lead fried itself off the post. The battery test worked for me.

 

[agedhorse]

I damage a speaker once. A tinsel lead fried itself off the post. The battery test worked for me.

Not the way you described for a single driver cabinet like what the OP asked about and what everyone else has been discussing.