i have a Alpine Type R 4 ohm 1500 watt sub and want to know wat kind of wire i should use to hook up the sub to the terminals on the inside of the box ?
I would recommend 12AWG for speaker wire. Sorry for answering your question earlier, based on power wire. Didn't read correctly the first time round that you wanted to know speaker wire.
As you said: Speaker wire, only comes in one size. But if the amp and speakers differ in output, go to a professional. Blown speakers are expensive.
Peace.