Ring Radiator Comparisons

[edgewound]

I saw this ebay auction a couple days ago, and emailed him about it. The auction is still up...

These are NOT JBL drivers... take a look at the phase plug, No annular slits! Round holes instead. Accepts a JBL or aftermarket clone diaphragm.

I have several JBL MR Series speakers with 2416H drivers, and none of them have "holes" in the phase plug like this pic.

I saw a pair of these same drivers on ebay awhile back, and knew they were not. I cut'n'pasted the pics from that auction into an email to JBL PRO Tech support. The next day, they confirmed with this reply:
Dear Rudy,

Definitely not JBL component. I asked around to see if anybody might know who made this, and it seems to be a Radian, but not absolutely sure.

Hope that helps,

Best Regards,

Alphonso H. Ochoa
JBL Professional
Technical Support

-----Original Message-----

From: Rudy J. Kleimann III
Sent: Thursday, September 08, 2005 3:48 PM
To: Ochoa, Alphonso
Subject: 2416 Drivers: JBL or fakes?

As Rob noted....these are JBL 2415 drivers. They were used in the old MI-series systems from JBL Pro. Some of the youngins at JBL haven't been around long enough to know any better....and all the veterans that built JBL are now long gone.....It's definitely not a Radian.

[louped garouv]

how funny....


but maybe the employee's name should be removed?


lest he become the running joke at company retreats....

heck they may start bringing him all kinds of legacy drivers and request that he ID 'em....

[Rudy Kleimann]

Well, fellas... don't know what to say

I guess I'll be pullin' diaphragms in my cabs to see what I've REALLY got. Happy to report, I've only replaced diaphragms in JBL compression drivers that were abused by others.

Robh, you are certain? Notice however, the drivers in both cases were advertised as "2416H". Note also the "-1" written on the magnet plate with a sharpie. Maybe 2416H-1? I have seen similar markings on 4" compression drivers too, with "-3", "-1", etc. I recently read somewhere (I think there was a posting on this forum) that these markings, as well as similar markings on the inside of the voice coil formers on diaphragms, were markings for production variations to optimally match drivers and diaphragms. I don't know; I've apparently been wrong once today already.

After all the drivers I've seen apart, JBL or others, I've only round holes once before, on a cheap no-name speaker with a 1" diaphragm where the sound wave did not pass through the magnet. ALL the JBL drivers I've had the diaphragm off of used the annular slits.

After finding this site several years ago, and learning of Jim Lansings' fight with Western Electric over rights to the annular slit phase plug design, and Altec going with thr radial slits, I never thought I'd see the day...

As for sympathy towards the JBL Tech support guy over his ignorance and the misinformation provided, should he suffer for his ignorance? :dont-know

[edgewound]

Well, fellas... don't know what to say

I guess I'll be pullin' diaphragms in my cabs to see what I've REALLY got. Happy to report, I've only replaced diaphragms in JBL compression drivers that were abused by others.

Robh, you are certain? Notice however, the drivers in both cases were advertised as "2416H". Note also the "-1" written on the magnet plate with a sharpie. Maybe 2416H-1? I have seen similar markings on 4" compression drivers too, with "-3", "-1", etc. I recently read somewhere (I think there was a posting on this forum) that these markings, as well as similar markings on the inside of the voice coil formers on diaphragms, were markings for production variations to optimally match drivers and diaphragms. I don't know; I've apparently been wrong once today already.

After all the drivers I've seen apart, JBL or others, I've only round holes once before, on a cheap no-name speaker with a 1" diaphragm where the sound wave did not pass through the magnet. ALL the JBL drivers I've had the diaphragm off of used the annular slits.

After finding this site several years ago, and learning of Jim Lansings' fight with Western Electric over rights to the annular slit phase plug design, and Altec going with thr radial slits, I never thought I'd see the day...

As for sympathy towards the JBL Tech support guy over his ignorance and the misinformation provided, should he suffer for his ignorance? :dont-know

FYI....the 2416H-1 diaphragm is a suitable replacement for the 2415H. These drivers are nearly 20 years old so to see a 2415H fitted with a 2416H-1 diaphragm is certainly no surprise. The 2415H has a copper round wire voice coil, the 2416H-1 has an aluminum edgewound voice coil, which is an upgrade fitment. Should Alphonso suffer? Not really....he should just learn from his mistake....I have been corrected here on this forum....and have learned new details about some things, and I've been JBL Authorized Service since 1988....17 going on 18 years. There's over 50 years of products to account for.

[Rudy Kleimann]

So... you are confirming that the driver pictured with round holes in the phase plug is a JBL 2415 driver?

If so, I learned something new today.

I knew that the 2416 diaphragm was a direct replacement. What I didn't know was that JBL made any compression drivers with this phase plug design

However, the 2 ebay auctions I saw these on still advertised the drivers as 2416H.

Just goes to show that ebay is the place where, as ebay puts it, "caveat emptor"...

[edgewound]

So... you are confirming that the driver pictured with round holes in the phase plug is a JBL 2415 driver?

If so, I learned something new today.

I knew that the 2416 diaphragm was a direct replacement. What I didn't know was that JBL made any compression drivers with this phase plug design

However, the 2 ebay auctions I saw these on still advertised the drivers as 2416H.

Just goes to show that ebay is the place where, as ebay puts it, "caveat emptor"...

Well...with all fairness to eBayers not educated in the internals of the 2415 and 2416 phase plugs....the only place the model number exists on these two variants is on the diaphragm assembly and nowhere else. So if a guy has a 2415H that's been rebuilt with a 2416H/-1 diaphragm, as far as he knows, that's what it is. But yes...as always with eBay "caveat emptor".

[Zilch]

"Real" 2416H-1:

[Zilch]

"Are ya STOOPID, Zilchster? 2407H is a TWEETER!"

Yeah, well, lookie here:

http://www.jblproservice.com/pdf/AE%...4212,95-WH.pdf

Also, here:

http://www.bmspro.com/products/4540nd.html

WT2 impedance curves on 2342:

1) JBL 2407H
2) BMS 4540nd-8

[Rudy Kleimann]

"Real" 2416H-1:

Thanks for the pic, Zilchster. That IS what a 2416 driver looks like from the diaphragm/phase plug side.

Like I said, I never knew or would dream that JBL would make a driver with anything but the annular slit phase plug design. I guess it is yet another sign of what Harmon might "require" to make a "competitively priced" driver even 15 or more years ago?

[Jan Daugaard]

So is JBL buying OEM drivers from BMS, or is it the other way round?

Or are JBL and BMS buying OEM drivers from a third, as yet unnamed company?

[Guido]

So is JBL buying OEM drivers from BMS, or is it the other way round?

Or are JBL and BMS buying OEM drivers from a third, as yet unnamed company?

Yeah! I could bet this 2407 is a BMS!!! Please Zilch some more pics to be sure.
Anyway it is one of the best BMS Drivers
As for your question Jan I'm almost sure the BMS drivers are made here in Germany.

[Guido]

Zilch, could you post an RTA plot of 2342 with BMS/2407? with several of your networks please?
Could you also post the same info with the 2344 and or even with the PT Waveguide 100x100 you sent me?

This would be MOST interesting!!!!

[Zilch]

Zilch, could you post an RTA plot of 2342 with BMS/2407? with several of your networks please? Could you also post the same info with the 2344 and or even with the PT Waveguide 100x100 you sent me?

Yup, that's the plan. This weekend, probably.

Preliminary report: 2407 sounds VERY good on 2342 biradial horn, the only combination I've really listened to thus far. Using NL200t3 crossover, I have it padded down about 6 dB more....

[edgewound]

Zilch,

Have you peeked at the diaphragm yet?

[Zilch]

Guido: Simple crossover for your horn is here:

http://www.jblproservice.com/pdf/AE%...4212,00-WH.pdf


Edge: I'm tempted, of course, but I don't wanna mess until the testing is complete here.