http://cgi.ebay.com/Used-PPI-DCX-500-1-mono-sub-amplifier-for-sale_W0QQitemZ110371923419QQcmdZViewItemQQptZCar_Amplifiers?hash=item110371923419&_trksid=p3286.c0.m14&_trkparms=66%3A4%7C65%3A10%7C39%3A1%7C240%3A1318