So I have an old Roland Spirit Bass 50 that I got when the local high school was getting rid of some of their older/broken/beat/surplus music equipment. The preamp section is surprisingly cool, with a regular bass/mids/treble EQ section as well as what appears to be a parametric EQ knob with switchable Q (narrow/wide/off). The problem? At some point, some teenage idiot poked holes in the speaker cone with a pencil or something. Is it possible to patch these? Or do a need a new driver? And if so, what driver would fit? It appears to be an OEM 15", as it's wider than 12". However, the cab portion of the combo is extremely shallow. Angled baffle board, so it's only 4.75" deep at the top, 5.75" deep at the bottom. Width and height of the chamber is 15.5".