Good day @audioguy85,
I am very happy with the 4309's. My room is small (3m x4m) . Placement is easy. They were AB-ed with a pair of ATC SCM20's. The JBL' s were chosen in 6-0 score in my set up. I used Metallica -Black Album, ACDC -Razors Edge, Loreena McKennit -Visit and Kari Bremness - ?Name for reviewing. My 4 daughters, wife and myself preferred the JBLs
The signal chain results in a sound I like. I have not detected sibilance, but, maybe its the music I listen to, lots of old school rock and metal. However, not detected on on Loreena McKennitt either. The Klipsch are good for the money but the price difference is reflected in the JBL. Also, in my small room, the back firing port of the Klipsch caused placement issues, even in my heavily treated room. Finally, tested the Klipsch against the JBL to see the benefit of the additional cost.
Speaker cables are a 4 wired Canare and split to biwire at the speaker end. It made a clear difference in sound. The AT 540 cart is very good in this set up. Phono stage is the built in MM stage in the Parasound Hint 6. TT is a KAB modified SL1200MK5 with Cardas tonearm wire, external PSU, strobe off function and and silicone damped trough.
As a second speaker, the Klipsch would do if a back firing port is not an issue.