375's NOT!!

[Woody Banks]

I purchased (on ebay) what was advertised to be a pair of 375 drivers. The seals were intact but the labels were missing. These were to go inside a pair of Hartsfields I have been laboring with. The drivers were terribly mismatched so I proceeded to investigate the reason why. With the backs removed, it was obvious that one driver was not a 375 but is a 360. It has a phenolic diaphragm that is slightly larger than the 375. Is the 360 the same as the 2482? The driver is black and not the typical gray from the pro line.
Woody:banghead:

[Oldmics]

Sorry you did not get what you were barganing for.Who was the seller?

I have not heard of a 360 driver from JBL,so I can not comment about its use.

There has been substancial discussion regarding these drivers.

Please follow the link for one of the threads that will give you the information that you are seeking and enjoy.For additional information try typing in a search for 375.

And again welcome.The link is below.

http://audioheritage.csdco.com/vbulletin/showthread.php?t=1308&page=1&pp=15&highlight=375

Oldmics

[Earl K]

With the backs removed, it was obvious that one driver was not a 375 but is a 360. It has a phenolic diaphragm that is slightly larger than the 375. Is the 360 the same as the 2482? The driver is black and not the typical gray from the pro line.

Well this was bound to comeup sometime .

Where did you get the 360 model number ? I've never heard of that one from JBL . Here are some of the 375 variants that I'm aware of ; from JBL, 375, 375AB, 375EX, 375FH, 375H, 375HP / from Dukane ; 5A360, 5P360 / from RCA ; MI 11427

- of the above, I know the 375HP is listed as using a phenolic diaphragm .
- BTW, the Dukane 5A360 used the D16R2440 diaphragm , the 5P360 used the 2482 diaphagm. "P" in Dukane nomenclature does stand for Phenolic. This designation is also continued into Dukanes' smaller diaphragmed offerings such as the 5P355 which used a phenolic diaphragm ( the D16R2470 ).

Obviously, JBL used to make/OEM quite a few 375 variants - at least one with a phenolic diaphragm. Reputedly, they had a model without a phase-plug used on floating "fog-horn" bouys. Hopefully your mystery driver at least has a phase-plug. If it doesn't , then you're completely out of luck unless JBL will demag your driver and reinstall all the proper parts ( they used to do this ) .

Radian (http://www.radianaudio.com/products/diaphragms/diaphragms.php4?viewT=diaphragms&viewC=diaphragms&viewI=) makes a replacement diaphragm for the 2482. It's available in 8 or 16 ohms . It will have a different response curve from your original/working 375 that uses the 2440 diaphragm in it .

I would, at the very least, obtain the intalled cost of 1 Radian 1282 diaphragm and then ask the seller to deduct it from the purchase price of your set of quasi 375s ( assuming you feel "willfully" misled in this transaction ) .

<. Earl K

[Woody Banks]

The drivers came from "Mike" @ nothernacoustics.com. They were shelved for four years before I caught the problem.
The 360 number I found on the inside of the coil former: It reads 5P 360HP.
It looks like I am the proud owner of a Dukane driver.
Thanks for the info, you were very helpful.
Woodyhttp://audioheritage.org/vbulletin/images/smilies/wink.gif

[Don McRitchie]

Just to be clear, the Dukane drivers are JBL's. They were manufactured by JBL under contract to Dukane. The only non JBL 375's are Ampex versions which they manufactured in their own facilities under license from JBL.

[Steve Schell]

I briefly owned one of the 375HP drivers; black crinkle paint, gold oval label. It was originally used as the high frequency device in a Leslie organ tone cabinet. It had a beautifully turned aluminum insert in the throat which pulled out and left a normal looking 375 throat. The frequency response died quickly above 5kHz., which prompted me to scrape out the wax seals and remove the rear cover to see what was going on. Turns out, it had a phenolic diaphragm.

As far as I could tell, it was an earlier version of what became the 2480 (later 2482) once the JBL Professional line was established.

I sold the driver on ebay, for... you guessed it... $375.00.