Alpine subwoofers are manufactured in a variety of types, each type is designed for the entry level to the pro audio car enthusiasts.  The Alpine Type-S subs will give you the most bass for your buck.  These subwoofers feature a shallow mounting depth, and only require a small amount of airspace making them suitable for a huge range of subwoofer boxes.  The Type-R Alpine subs are made to bump.  These subs can handle a huge amount of wattage but don't worry they don't sacrifice any sound quality due in part by the high quality materials they are made from.  The Alpine Type-X subs provide clean accurate bass, while handling upwards of 1000 watts.  These pro-audio subwoofers will provide the most accurate sounding clean bass, while handling all the power your amps can throw at it.