Well I've just logged about 20 hours of music onto my newly aquired 7's. I'll start by saying that when I first opened the box and pulled them out the finish was great for the money. They felt solid and the piano black was near mirror like to my eyes. When I first heard the reviews of how good these speakers might be, I was skeptical of the build quality. But since receiving them I am very pleased.
Now for the good part. The speakers sound better than any I have had in my home. I was really impressed with the bass accuracy from such a small driver. I don't think Polk could have done a better job porting, sizing and doing whatever else they did to get this right. Every recording I've played sounds more accurate than alot of speakers I have listend to in stores and at friends homes, and some friends have some very nice speakers. I had Citation 7.2 LCR up front and they were really good for HT but for music everything sounded sub-par for a speaker that retailed for nearly 700 (THX/80hz built-in), just not a very musical speaker in MHO. Vocals on the Citations were always harsh and at high volume earpiercing at times. On the contrary the LSi's are very musical. So musical that I don't even use my sub for now, when I do the mids and lows just get garbled and vocals sound like crap. With all that said thus far, my good recordings sound awsome and the poorer recordings make me hit eject and put something else in. Just a peev of mine; love great recordings and great music but when I heard Californication by RHCP I wanted to toss it at the producer.
Vocals are great and the lower end of that is well handled by a good driver with much thought into cabinet design. Still a sub is still required at high db's as the 5 inchers just weaken in this area as the you reach peak levels; I just haven't found the right one yet and haven't given it much thought in the past. That will change in the near future though. : )
So finally, the tweeter is super smooth. Cymbals are spot on and exactly where they are supposed to be. On good recordings the vocal transition form tweeter to woofer is near seamless and very, very smooth. With that said, poor vocals on poorer disks will just sound bad, and it's not the speakers' fualt... it's just what was produced, I honestly can't think of another way to put it.
Lastly, this Polk will give you accurate sound reproduction and accuracy as a good speaker should and won't steal you wallet. It won't correct poor recordings when the lower frequencies aren't there, it won't make hiss in a recording go away and it won't make that scratchy vocal sound smooth. It will reproduce a recording really well and give you an idea of what you are trully listening to and you can't ask much more from a speaker of this size and price tag.
--don't harrass for spelling or gramar
-----I will review for HT in a couple of weeks, Citations involved