View Full Version : 4345 References Thread

06-01-2007, 05:57 AM
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 (http://audioheritage.org/vbulletin/showthread.php?t=10490). (http://audioheritage.org/vbulletin/showthread.php?t=10490)

Bo Putnam did a 4345 monitor plan thread (http://audioheritage.org/vbulletin/showthread.php?t=314).

There's a Techbot thread detailing 4345 Enclosure Plans (http://www.audioheritage.org/vbulletin/showthread.php?t=11856)

Here's another Techbot thread: 4345 System Information designer post (http://www.audioheritage.org/vbulletin/showthread.php?t=10613) (with comments from Mr Greg Timbers)

(Below photo credits:
4345 barefaced image courtesy of Ian
4345 flanking 4313Bs and TV (http://audioheritage.org/vbulletin/showpost.php?p=4681&postcount=19) courtesy of Bo Putnam
Restored 4345 with black baffle (http://audioheritage.org/vbulletin/showthread.php?t=16275&highlight=4345&page=2) courtesy of Riessen

06-01-2007, 07:02 AM
The oldest Pro price list I have only goes back to April of 1977 -
http://audioheritage.csdco.com/vbulletin/showthread.php?t=349&highlight=studio+monitor+pric e+list (http://audioheritage.csdco.com/vbulletin/showthread.php?t=349&highlight=studio+monitor+price+list)

Thanks, Giskard!

Here is a Link to 1981 Model 4345 Monitor (http://www.lansingheritage.org/html/jbl/specs/pro-speakers/1981-4345.htm) in Library section of this website.

Please read the Field Guide to the JBL 10 inch Midbass driver 2121 2122 2123 (http://audioheritage.org/vbulletin/showthread.php?t=16962) for more information on the driver that transitions the sound between the large woofer and the horn/compression driver.

The drivers specified for the model 4340 & 4341 are listed in the graphic excerpt posted below (chart posted courtesy of JBL). Note the similarity in drivers between the 4340/41, the 4343, and the 4345.

06-02-2007, 10:53 AM
Crossover Notes

3145 - crossover used in 4345 (http://www.jblproservice.com/pdf/Network%20Schematics/3145%20Network.pdf) (final version of the 4 way crossover used in this series)

Ian posted this excellent photostudy - JBL 3145 stock crossover.- A pictorial (http://audioheritage.org/vbulletin/showthread.php?t=13930&highlight=4345+crossover)

Charge-coupled 3145 crossover network - Schematic diagram below courtesy of Giskard
(I flipped the color scale & rotated it to make it easier to see)
(I can't find the original thread I saved it from, at the moment, but I'll post the link when I find it)

06-02-2007, 10:55 AM
This is designed to be a longer term references to other resources here and outside on the web. We are trying to keep the signal to noise ratio high.

To keep the thread "on topic", please give me the next few days before posting ANY replies or comments here.

Your on-topic images, information, insights and links are most welcome and I'll give you credit for your contributions.

Your PMs are most welcome.

Thanks for your help!

Heather James

Image courtesy of Bo Putnam (http://audioheritage.org/vbulletin/showthread.php?t=314)

06-24-2007, 07:34 PM
The original thread is courtesy of Giskard- circa April 2005 http://audioheritag (http://audioheritage.org/vbulletin/showpost.php?p=52286&postcount=124)e.org/vbulletin/showpost.php?p=52286&postcount=124 (http://audioheritage.org/vbulletin/showpost.php?p=52286&postcount=124)

In that post, Giskard said:
Here's a Solen/Mills parts list along with the schematic from post 100.
You can substitute the Solen resistors if you wish.
They run something like $0.50 instead of $3.50 (Mills).

(Note HJ - I inverted the color scheme of the schematic to make it easier to print)