This thread is an index to various other threads and references on the larger JBL 4-way monitors. These threads do not include the larger dual woofer monitors such as the Model 4350, which had other design constraints.
The 4340 and 4341 (1973-75) were the first in a series of 4-way Studio Monitors that were followed (1976) by the larger and better known 4343 and which culminated in the 4345 monitor (18" woofers). The 4345 Monitor is very well documented in threads on the Lansing Forums, and has many fans here.
We have a thread called The JBL 4345 Club.
Bo Putnam did a 4345 monitor plan thread.
There's a Techbot thread detailing 4345 Enclosure Plans
Here's another Techbot thread: 4345 System Information designer post (with comments from Mr Greg Timbers)
(Below photo credits:
4345 barefaced image courtesy of Ian
4345 flanking 4313Bs and TV courtesy of Bo Putnam
Restored 4345 with black baffle courtesy of Riessen