Banana plugs are great for experimenters and folks who make a lot of changes, but they don't offer much contact area with the barrel they fit in to. You want maximum contact area. After all, there are two ends to the wire and the net effect of both connections must be considered. While I use many banana plugs and buy dozens every few months, I know spades or bare wire will give me a better connection. Remember, bare wire will squash down and fit the contacting surfaces very well. Copper is rather soft and will flow over time, loosening the connection. (That's why there are electrical fires in old houses.) Tighten them up every year or so. Spades seem to offer a good connection, but how do they attach to the actual wire? You have two connections on each end! The wire to the spade, and the spade to the speaker terminal (not to mention the terminal to the lead that actually goes to the actual speaker!). So, considering there are two connections inside the speaker "box," it is best to use bare wire and tighten the connecting mechanism really tight. The "tinning" you hear or read about is just to keep the many strands of wire in many types of cable from separating as the connections are tightened. A good idea. Use "silver solder."
