Finally Got the JBL 4345

[Dev]

Hi, Greetings to everyone. After a long search I found a pair of 4345 and now waiting for the recone kit to arrive. Meanwhile thought of getting rid of that infamous switch in the crossover.
Will share the pictures before I start disturbing you guys with my questions.

[Dev]

The crossover

[Dev]

Hi, the stock caps in the 4345 was replaced with Clarity and Auricap . The Switch was bypassed and the binding post changed.
The initial results are promising even without burn in. Now need to replace the L pads with fixed resistors.
Thanks everyone for your kind help and a special thanks to Ian….you are indeed the “ YODA”
Regards
dev

[Chas]

FWIW, I’m still using the L-Pads in my 4345’s after owning them for nearly twenty years, but do rotate them every year or so. If you’re really keen on replacing them with fixed resistors, I would wait a year or two. It can take a long time to get four ways dialed-in.

[Dev]

FWIW, I’m still using the L-Pads in my 4345’s after owning them for nearly twenty years, but do rotate them every year or so. If you’re really keen on replacing them with fixed resistors, I would wait a year or two. It can take a long time to get four ways dialed-in.

Hi Chas, I am planning to change the L pads only for the mid freq, since one L pad is giving lot of trouble.
Regards

[Chas]

Hi Chas, I am planning to change the L pads only for the mid freq, since one L pad is giving lot of trouble.
Regards

Aha, got it. Best of luck with your 4345’s, they continue to amaze me after decades of service here.

[RMC]

The lens provide proper sound dispersion in the room, so they are important...

If you cannot find the right JBL lens you may want to look at McCauley Sound they made similar aoustic lens that may also be offered on EBay?

Richard

[Dev]

The lens provide proper sound dispersion in the room, so they are important...

If you cannot find the right JBL lens you may want to look at McCauley Sound they made similar aoustic lens that may also be offered on EBay?

Richard

Thank you RMC, Kenrick sound offers lens on eBay. Will also check McCauley Sound.
regards

[Dev]

The Switch in the Crossover of JBL 4345.
how to wire it directly without using this switch? I went through Warpigs thread , but that was a different kind of switch please advice how to go about it.

Thanks in advance.

[Dev]

Hi , can anyone let me know how to get rid of the Switch and wire it directly? Or just cleaning it with deoxit is good enough?
thanks

[Odd]

I have no experience with this filter but here is the wiring diagram.

You can see here what the switch does.



3145 Network.pdf

[Earl K]

By far the simplest approach is to bundle the mess off to someone who actually recognizes what they are looking at ( and then have that same person add 6 bypass wires at the proper locations // essentially doubling up the connections being made by the switch ) .

I would add//solder these bypass wires onto the lower "L-shaped" leads that are themselves soldered into the ( unseen ) circuit board traces .

Those switches are too heavily corroded for cleaner ( IME ). Cleaner won't remove that black oxidization ( only applied abrasion >> not recommended since the switch will fall apart under the duress of filing ).

[Dev]

Thanks Odd for the diagram and thanks Earl, will sent it to a service guy. I don’t think I can do it myself.
Any pictures of how the wiring is done?

[Earl K]

Thanks Odd for the diagram and thanks Earl, will sent it to a service guy. I don’t think I can do it myself.
Any pictures of how the wiring is done?

There's no pic here at LHF ( that I know of ) that shows how to hardwire the switch ( into the input mode of your choice >> & BTW once you add the necessary 6 wires one is stuck with the choice of input mode made ).

If a tech ( or anyone else for that matter ) can't figure out for themselves ( which 6 pairs of tabs get hard-wired together for either input mode ) then they have no business mucking about inside these boxes crossovers ( IMO ).

[Dev]

Hello all, I bypassed the switch and wired it in Bi amping mode ( external x over) and I am not using external x over for the LF at this point of time. So I am using Jumpers in between the binding post and using a single Tube amplifier , but the system lack dynamics ……
since I wired it in bi amp mode , the signal to the LF doesn’t come through the internal crossover? ( though I use jumpers between the binding post) Do I need an external crossover and an amp for LF if the switch is bypassed and wired in external x over mode?
Thanks and Regards