dual voice coil....no you dont need 4 channels...u could use mono amp if you wire it corectly....or a 2 channel which gives you less options but is easier....for help onwiring in series or in paralell check this out
if you buy an amp that can handle a one ohm load then you can wire it in paralell it will give you the most power but if it is not one ohm stable then it will burn fast...there are a variety of ways to wire 2 DVC subs....depending on what amp you have...have u already bought one....?