Please identify these speakers, Type 4502 Enclosure

[Hamburger]

Hello!


I’ve been reading in your excellent forum for quite some time.


Now I need your help:


I recently bought two speakers. A friend of mine bought them years ago in a pitiful state from a recording 6790167902679036790467905studio here in Hamburg. They had been in storage for at least ten years. The friend had one of the woofers reconed in a service center.


Now I’d really like to know your opinion, what these speakers exactly are.


Don’t judge by the outer appearance, the friend painted them in white (instead of the original grey) and the front was black before.


On the back there is the badge saying „Type 4502 Enclosure“ and there are two crossovers, a LX5 and a N8000.


Please take a look at the pictures.


The way I understand it, these originally were 2-way speakers that were ugraded with the original crossover and a „citrus press“. Then the 2405 had been installed instead of that.


Did JBL offer an official upgrade path of a 4502 to this type?


What is the comparable JBL-Type then? 4333?


Final question: The LX5 crossover is filled with something like resin. On the outside there is something sticky like modelling clay (it even smells like that). Is this normal? Or did the capacitors leak?


Thank you very much for your help! Any hint is appreciated.


Best regards, Henning

[Hamburger]

6790667907679086790967910

[grumpy]

4502 is the part number for the cabinet only.

Looks like someone used JBL parts to make a 3-way system.

I believe the 4320 (older 2215/2420 based monitor) used the 3110 (800Hz).

I don't recall an end-product 43xx monitor that used a potato masher (2305) with LX5.

The goo inside is likely wax. Outside? Perhaps clean them off.

So what you have is not a 4333 or even equivalent without some changes.

[mech986]

4502 is the part number for the cabinet only.

Looks like someone used JBL parts to make a 3-way system.

I believe the 4320 (older 2215/2420 based monitor) used the 3110 (800Hz).

I don't recall an end-product 43xx monitor that used a potato masher (2305) with LX5.

The goo inside is likely wax. Outside? Perhaps clean them off.

So what you have is not a 4333 or even equivalent without some changes.

I agree, this was probably the 4320 type originally based on the DS50SMS7 of the 60's. The 4502 cabinet with overhanging corners is the giveaway to this original 2 way system. This system morphed into the later 4331 (4330 was a biamp only 2 way) with slightly different woofer (2331A) and more modern cabinet (4503 grey and 4503WX walnut). The addition of the 2405 and appropriate crossover was a typical modification into the 3 way 4333.

http://www.lansingheritage.org/html/jbl/specs/pro-speakers/1967-d50sm7.htm

http://www.lansingheritage.org/html/jbl/specs/pro-speakers/1972-4320.htm

http://www.lansingheritage.org/html/jbl/specs/pro-speakers/1974-4330-4331.htm

http://www.lansingheritage.org/html/jbl/specs/pro-speakers/1977-4331-4333.htm

[Hamburger]

Thank you to both of you!

Yes, that evolution of my speakers seems logical.
And the crossovers look normal to you? The components were drowned in wax at the factory?

That explains why there aren't any pictures of opened JBL Crossovers. They sound great, but they don't look like high-end equipment.

:)

Best regards, Henning

[audiomagnate]

Thank you to both of you!

Yes, that evolution of my speakers seems logical.
And the crossovers look normal to you? The components were drowned in wax at the factory?

That explains why there aren't any pictures of opened JBL Crossovers. They sound great, but they don't look like high-end equipment.

:)

Best regards, Henning

The wax prevents oxygen and moisture from getting to the crossover parts, in particular the capacitors. This help delay deterioration. It's a good thing.

I know I've seen that hinged tweeter before many times, I just can't seem to remember where.

[mech986]

The wax prevents oxygen and moisture from getting to the crossover parts, in particular the capacitors. This help delay deterioration. It's a good thing.

I know I've seen that hinged tweeter before many times, I just can't seem to remember where.

The hinge looking thing is a regular 2405, likely alnico without the usual 4 hole mounting flange, much like the 075/2402 alnico. those were secured using the horseshoe clamp with the tightening bolt to lock it onto the baffle.

the larger monitors (4331/3 and L300 types) had big rectangular boxes with hard point wired crossover components (mostly caps and inductors) embedded in wax to prevent spurious vibration damage and provide oxidation prevention.