Lot of 2 Roland PDX-6 and 2 Roland PDX-8 Drum Pads

Includes a pearl drum key

Used condition

I am not at all music savvy and have never used an electric drum set before.  I plugged them in and the outer rim and white portion are highly responsive.  The actual pad is highly responsive by the "V-Drum" logo on 3 and by the "Roland" logo on one of the PDX-8's (the one with the pad the opposite way).  From what I've read, this could simply be a setting that needs to be changed on the brain/module, tightening/loosening of the heads, or they could need replacement cones/sponges.  I'm not sure and do not have the time to put in to figure it out.  Sold as-is with no returns.