So your ready to compete but which event are you gonna win and which one are you gonna get left in the dust. There are many events out there to enter. Most follow the same basic rules and format, what does differ is the classifacation the competiors are in.

Db Drag Racing classes are determend by quantity of subs 1-2, 3-4, 5-6, 7-8, and 9+. So a competior with 2 10 inch subs, could run against someone with 2 15 inch subs. It is inportant to note there is no limit on the power or amount of amps that can be used. (any CD may be used)

USAC similar to db drag but competiors are grouped by RMS (root mean squared) wattage to entire car audio system. This is an overall fair way to judge however the use of cheater amps, and advanced wiring technics are always a possibility. (official CD must be used)

USAC Outlaw Spl same as USAC but any tweaks may be used, unlimited Batterys, Opening doors or trunks, Walls, or even taking all interior part out and replacing with wood or other damping material. (official CD must be used)

IASCA SQ is more of an over all car sound compation where competiors are grouped be overall wattage (Mid, Subs, and High range amplifers, the maxamium Spl you can hit is 150.0 db. (official CD and Track must be used)

Iasca IDBL. is more of a Db Drag format, Competiors are grouped together based on overall surface area usally 11-20, 21-30, 31-40, 41-50 and so on for example, two 10 inch subs or one 12 inch subs are in the same class as one 15 inch sub or one 18 inch sub but 2 12 inch subs would be in the same class as 2 15 inch subs. the posabiltys are endless in this type of format, you could enter the 20-30 class with 3 10's or 2 12's or 2 15's or even  1 12 and 2 8's whew..... thats a lot off diffirent combinations. just a quick hint look for long excursion subs in these events. (offical CD and Track must be used)
Db drag rules
USAC rules
USAC Outlaw Spl rules
Iasca Rules
IDBL rules
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