What should I do?

[blackraven]

Have you listened to the speakers that you want to buy? If so, do they sound better than the ones you currently have? If so then get the speakers. Otherwise buy the onkyo receiver, take it home and if it doesnt make a big difference return it. But IMHO, I think upgrading speakers is the way to go. Changing speakers will change the sound of your music whether its for the better or the worse. An amplifier may or may not change the sound of your speakers. And with lower end speakers, I don't think the Onkyo will make that much of a difference. You may get deeper base with the onkyo but is that what you are looking for? Larger speakers will aslo do the same thing.

Hope this helps some but in this hobby there are many opinions because audio is so subjective.

I just looked at the specs of the 2 models of the JBL's and the 610's freq response dips down to 55Hz vs 75 for your current speaker. To me thats a huge difference. If your looking at speakers in this price range, you should check out the infinity primus 160's. They are very crisp and clean sounding and can be bought for about $75 each on sale.