Recently I've been thinking about buying a 7 band equalizer or similar for my stereo system. I don't know much about equalizers, though. It would be connected to an Onkyo TX-8511 stereo receiver. It sounds good for the money, but obviously it isn't high end, so I'm wondering if spending a couple hundred bucks on an equalizer would boost the sound quality significantly or would be a waste of money.

If it is worth it, what would be a good choice for an equalizer?