I just picked up a pair of RTA 15TL's from a fellow member and they are in very good condition. I was curious to hear the next generation speakers Polk came out with after the SDA series. They seem to be very good in the mids and overall a very good speaker. The one thing I noticed was how similar they sound to my SRS 3.1tl speakers. The slight difference seems a little bigger bass in the 3.1tl's. I am curious to know why Polk used a woofer coming out the back of the speaker. I have not seen to many reviews of these speakers and wondered if the audiofile reviews were favorable in the day of the RTA 15tl's.