I bought a 200s cab with Radioshack 15s in it for $100. I opened it up and the port ducting was all jacked up. Like someone hit it with a sledgehammer to break the duct enough to fit the Radioshack speaker in. I cut out the busted up duct with some type of electric saw I found in the garage and put in some Eminence Big Ben's.
The cab is all jacked up but it still kills it. I run it for guitar paired with a 4x12.
If I was able to retain the port ducting and put in the Big Ben's how do you think it would sound different??