Wondering if/how to improve on old JBL speakers

funkpelts
funkpelts Posts: 6
edited August 2005 in Speakers
I have Polk R15's for rears and a CS1 for center. My receiver is a Denon 2805. I have JBL model 2800 for my mains. I want to replace these but only if i can improve on them. What I was considering RTI series but I am not sure if this is an improvement. Does anybody know how this would compare?
Oh yeah and I replaced the tweeters with Morel MD20 model or something like that.