The poor thing is sitting in the garage looking very sad and lonely. I should have sold it years ago but being my first ever cab, I can't bring mysef to do it. It's a Fender BXR 115 with a single 15 in it. But the speaker doesn't work, which is a good thing because I didn't really like the sound. It was originally an EOM Eminence driver of some sort. The cab is huge, 173 litres (6.1 cu feet) so......... I'm thinking about replacing the 15, plus adding a 5" driver for midrange, + a horn. Ideally I'd like a final nominal impedance of 4 ohms and I'd use this as a stand-alone cab. At this stage I'm looking at the Delta Pro 15 which comes in at 8 ohms. I have absolutely no idea how to approach the midrange 5. I've spotted a couple of locally made drivers that have a Fs of 550Hz and recommend a 12db crossover at 800Hz. They're 8 ohm speakers so my first instinct is to wire it to the 15 in parallel to get a 4 ohm load. But I'm not sure if midrange drivers are treated like horns in that they don't affect the overall nominal impedance? Also has anyone got any suggestions for a 5" midrange driver?