Hello, I am having a good friend build a 1x15 cab to go with my newly acquired Fender Bassman 400 combo. I see that Fender has a 115h cab that can be used with it, but I would rather build something with a better speaker. My question is... What speaker should I go with? I don't want or need anything SUPER expensive.. But something middle of the road would be nice. Thoughts? Opinions? Thanks!