With the same power, the single 18 would have a cone area advantage. The 2 12's would have more motor to dissipate heat though. It would be close, not enough of a difference to really say one would hands down be louder.
With the same power, the single 18 would have a cone area advantage. The 2 12's would have more motor to dissipate heat though. It would be close, not enough of a difference to really say one would hands down be louder.