How do you test to see what speaker wire is positive and negative?

To determine which speaker wire is positive and which is negative, you can use a simple method involving a battery. Connect the two wires to a small battery (like a 9V battery) briefly; if the speaker cone moves outward, the wire connected to the positive terminal of the battery is the positive wire. If it moves inward, the wire connected to the negative terminal is the positive wire. Be cautious not to leave the wires connected for too long to avoid damaging the speaker.