Last year I had new speakers installed and they've got really good sound quality. However, I've been listening to more bass filled music lately, and I have no bass in my system at all. I've got about $650 and I have no clue about sound systems. I'd be extremely thankful if anyone knowledgable could recommend what would be best for my money. My car is about the size of a Tahoe, or Explorer. Please recommend and amp and wiring too. Thanks very much. I appreciate it!