Stoo - snicker and weep both if ya want, but don't blow yer cone
and notice that with audio "ground" is actually "common"
I don't know about "all" speakers, but I do know that Hardy's are differentiated by wire color, as most I've seen [usually red and black or copper and silver] - apply yer 12V battery to that + and - and see what ya hear from the radio - an audio signal is not "voltage" in the sense that Hardy suggests, to be checked with a battery
Bill
