Here is a question that I have been meaning to ask for about a year now.
When I purchased a pair of 2012H drivers, they came with an aluminum cap mounted on the back of the magnet.
Does anyone have any ideas as to it purpose?
Thanks,
Baron030
Here is a question that I have been meaning to ask for about a year now.
When I purchased a pair of 2012H drivers, they came with an aluminum cap mounted on the back of the magnet.
Does anyone have any ideas as to it purpose?
Thanks,
Baron030
I'm not sure what to look for. All that I see is the cast iron back plate that has the JBL logo, vent hole and horizontal striations cast into it. This is an integral part of the magnetic return structure, and part of every ferrite magnet motor.
Regards
Don McRitchie
It is aluminum and held to the ferrite magnet structure by glue. When I bought mine they fell off during shipment, not sure if it is purely decorative or part of the acoustic structure.
Regards
AL
The 2012H is a midrange/midbass driver in the VS2210,VS3215, VS3218 system. The aluminum cover you're referring to is probably the back loading chamber for this horn loaded 10". Maybe yours came from a parted out system?Originally Posted by Baron030
Your picture just shows the raw frame 2012H back plate...which is typical for that driver.
Edgewound...JBL Pro Authorized...since 1988
Upland Loudspeaker Service, Upland, CA
US Speaker sells the raw 2012h for about 249.00. Besides the VS series. it is also a great midbass for a DIY 4 way system.
AL
I owned 2 2012 speakers. One had this "backcap" the other not.Originally Posted by edgewound
The backcap is just cosmetical. It's no part of the magnetic structure
Can't find the pics
I think you are refering to the model/serial number plate on units sold as individual drivers. On drivers that need it there is a vent in the center of the plate, others are completely covered. They serve no purpose other than ID. OEM drivers and units sold to other manufacturers are sold naked and usually without the rubber donut over the exposed magnet that prevents chipping. Usually the model # has a PL (ie. 2226 HPL). I read it as H= 8 ohm and the PL as private label but that info is worth what you paid for it I really don't know.
4406, 4412A, L100, L100t3 (3 pair), L1, L7, 4645C, 4660A, 4695B, SR4735 and various DIY JBL Pro loaded systems.
Thanks everyone for all your feedback.
When I purchased these drivers from US speaker about a year ago, my first thought, when I opened the boxes was that they were magnetically shielded.
But, a quick test with a screw driver proved that was not the case.
Then, I thought that maybe the aluminum caps had something to do with the magnet's circuit. But, that really does not appear to be the case.
So, the aluminum caps really are just cosmetic.
Thanks, Mystery Solved.
Baron030
I'd really love to see a photo of that aluminum cap. I'm having a hard time believing that it's just cosmetic....why would JBL want to cover that beautifully cast motor structure?Originally Posted by Baron030
If it reaches all the way to the speaker frame mounting flange and covers the cone, then it's purpose is to be an acoustic loading chamber for midrange isolation.
Can you post a pic? I'm Reeeaaallyy curious....
Thanks Baron.
Edgewound...JBL Pro Authorized...since 1988
Upland Loudspeaker Service, Upland, CA
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