I recently received a sub and wanted to try and test it to make sure there are not blown voice coils or anything else wrong with it before is spend the money for an amp or it.
Push up/down on the cone to see if the coil rubs.. be carefull because some subs have tight gaps and if you do not push exactly strait you may cause the coil to rub yourself..
T
ouch a 9V battery to the terminals and watch the cone pop if you don't have a DMM to check for continuity..