The 4343 gets a lot of air play but we don't hear much about the 4340/4 on the forums so I went looking on the JBL web page and found this data.

http://www.jblproservice.com/pdf/Sys...r%20Series.pdf

Aside from being a biamp only (4340) or full passive version (4341) the 2231A ands 2121 is the main difference in the 4340/41 (as did the 4343) while 4343B used the 2231H and 2121H

The top panel is also non removable in the 4340/41 and the enclosure is slightly shorter at 37 3/4, and deeper 19 3/4 and less wide 23 1/2 than the 4343 at 41 5/8 high, 25 wide and 17 1/8 deep. The dog box of the 4340/31 is 0.3 cu ft3 and the 4343 0.50 cu ft3.

What I did find interesting was the crossover schematics.

I am curious as to what driver polarity orientation was intended for the 4341?

The location of the 1.5 uf capacitor shunted after the 4 uf capacitor in the Hf bandpass filter is interesting rather than after the 0.25 Mh choke ? It must have been an interesting load for amplifers before they added the 4 ohm resister.

http://www.jblproservice.com/pdf/Net...%20Network.pdf

http://www.jblproservice.com/pdf/Net...%20Network.pdf

If anyone owns either of these versions some pics and discussion would be most welcome.

Ian