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View Full Version : Did JBL 4300 series "B stock" exist?



old_4312
12-03-2018, 09:57 AM
My right channel virgin 4312 from the early '80's (maybe late '70's) started buzzing. It was the LE25-2. I meticulously disassembled it to find a mess inside. How it ever worked all this time is beyond me.The VC former was crooked on the spider, the coil on the former was also wound crooked and there was glue residue in the gap!. This was an all original LE25-2. Did JBL sell "B stock"? I paid 900 bucks for the pair back in '84. Not happy right now. I also have little puddles of red goo at the bottom of the cabinets from the 2213H's. Can this be replaced with PVA glue? So not feelin' the JBL love at the moment....
Please advise....

Ricpan
12-03-2018, 10:12 AM
Not sure about B stock but I'm not what I used to be 45 years ago if you get my drift. Lots of good vibrations in that time.

Rick

Ian Mackenzie
12-03-2018, 10:36 AM
I am not aware of B stock so l donít think you have been stooged.
However it had been documented that when JBL has changed ownership quality suffered.

It would appear your LE-2 tweeter has operated up till now and you didnít detect any issues. I note you did some measurements previously. Did you ever compare the L&R enclosures?

Have you been in contact with JBL about your concern?

Looking at it another way most loudspeakers built in the early 80ís have required repair or simply have stopped working by now and are landfill.

About the goo are you able to post pics?

old_4312
12-03-2018, 12:03 PM
I am not aware of B stock so l donít think you have been stooged.
However it had been documented that when JBL has changed ownership quality suffered.

It would appear your LE-2 tweeter has operated up till now and you didnít detect any issues. I note you did some measurements previously. Did you ever compare the L&R enclosures?

Have you been in contact with JBL about your concern?

Looking at it another way most loudspeakers built in the early 80ís have required repair or simply have stopped working by now and are landfill.

About the goo are you able to post pics?

Absolutely!
Given it's been over 30+ years since I purchased them, I doubt JBL would be interested. They no longer make parts for the tweeter anyway.
The tests I did back in '06 were LF tests. Even though I did RTA the speakers in the room, even with hand matched crossover caps, I was never able to get a perfectly centered mono image.
I think this was the reason. Given the issues I have at 90 Hz and the low end in general with a 8 ft. ceiling, I just decided to live with it. The truth didn't get exposed until the tweeter started buzzing. I'm posting pics of the red goo on the speaker frames and of the LE25-2 VC.

old_4312
12-03-2018, 12:31 PM
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So, can you use white PVA glue to replace the red JBL goo?

JeffW
12-03-2018, 02:11 PM
Different animal altogether, from a different era of 4312, but back in 2011 Harman had a close out sale on a bunch of stuff. I bought a pair of 4312D (black vinyl finish) for $327/ea and they were labeled as B Stock when they got here. Seem to play fine and they are in a non-critical garage system application. Not sure if they sold B Stock back in the heyday of the original 4312.

Ian Mackenzie
12-03-2018, 07:41 PM
The spider looks buckled. (It’s like the effect of a long unhappy marriage..Lol)

I am not sure why the spider has buckled/or the winding uneven.
It could be long term deterioration, the effect of changes in heat or humidity or something else after being in storage.

I think others can weigh in on the hoop. Do not do anything yet. I recall they can do this.