Ok. I have a Ba-115 that has a blown speaker. It came with a 4ohm 15 wired with a tweeter. I disconnected the tweeter, and am looking at a cheap 8ohm 15 to replace it with. Will volume decrease significantly with the 8ohm? Does the tweeter when hooked up affect ohms? What ohms does the head operate at? I basically want to fix it as cheap as possible so I can sell it.