Im wondering if the Yamaha 1500/2500 reciever would go good with my current set up. Its the next thing on my list to get a new reciever so any feed back would be great
JBL speakers are fairly revealing and not real warm. Therefore when you match them with a Yamaha RX-v1500/2500 you may end up with a slightly harsh, clinical sound, especially during playback of music. However, this may sound good to you, so if it is possible you need to audition the speakers with the receiver.
I would personally not match a JBL, Klipsch or Athena speaker with these Yamaha receivers. I would match it with more of a laid back speaker such as Paradigm or B&W.
Marantz, Pioneer and Harman Kardon lean towards a warm sound, which would work well with the JBL speakers. I'm not sure which have THX certification, if that is essential for you. In my opinion THX certification is overated. Others may chime in on this if you would like some reasons why.
I don't particularly like the Pioneer Elite line, however it may work well with your JBL's. The Marantz SR7500 is very nice, and the Harman Kardon AVR7300 is excellent although it is out of your price range.
In my opinion, any of the receivers in your price range from these companies would have a noticably fuller sound with your speakers than the Yamaha RX-v line.
I agree that THX cert is overrated, however I do like the pioneer elite line, and would suggest you check out the pioneer elite 56. Marantz and HK are also good matches, so listen to them all and see which you prefer and has all the inputs that you need.
I own Klipsch reference speakers. Had them paired with a yamaha receiver. While it wasn't the worst sound I've heard it was definitely bright. If you plan on ONLY watching movies and have a decent sub, this sound may actually work quite well. However, I have exchanged the Yamaha receiver for a Marantz Sr-7400 and am happy with the change. You may lose a very slight amount of 'excitement' with action movies, but over all it is definitely a more refined, pleasing sound. I have found the output a bit surprising with the Marantz as it doesn't seem to have the strength of the Yamaha RXV 650, however still more than I will ever need. I also prefer the build quality.
Hope this info helps when choosing a receiver for your JBL's