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hightechhick
08-28-2008, 10:10 AM
:( Help.

Does anyone know of a thread or link that describes the proceedure to replace a JBL D8R2425 diaphragm in a JBL 2426H Compression Driver?

speakerex
08-28-2008, 11:03 AM
DIAPHRAGM INSTALLATION FOR MODELS 2425, 2426, 2427, AND 2445*

1. Fold piece of masking tape lengthwise around a cardboard digger with adhesive side
exposed. Insert in gap and rotate to clean out debris. Continue cleaning until tape is
clean when withdrawn. Inspect visually with magnifying light. Inspect new diaphragm for
defects or damage. Using an air gun blow out the gap for any debris that was not visible.
2. Remove cover gasket to expose JBL name that is stamped into the top plate. Using both
hands, carefully position diaphragm mounting holes in alignment with top plate mounting
holes and input terminal with polarity marking aligned with JBL name in top plate. Polarity
marking for 8 ohms will be green, and for 16 ohms the marking will be red. Warning: do
not rotate the diaphragm while the voice coil is in the gap. With mounting holes and
polarity marking positioned correctly, carefully lower the diaphragm into top-plate recess.
Be sure the base of the diaphragm mounting ring is positioned flush to the surface of the
top-plate recess. Insert mounting screws and hand tighten.
cathy@speakerex.com

hightechhick
08-30-2008, 10:03 AM
Thank you for the speedy reply!

I was an analog tech from long ago RCA. I get around on the web just fine, but this is the first discussion group I have ever joined. This seems like a friendly place with lots of knowledgeable people.

Once the diaphragm is replaced, is there a final test procedure involving an oscillator or other test equipment?

Thanks again,
-HTH

speakerex
08-31-2008, 12:40 PM
yes we test all speakers both before and after the repair to be sure that they 1) need the repair and 2) measure up to the appropriate specs.

readswift
09-01-2008, 10:48 AM
if there was reputation meter on this forum , I'd click like no tomorrow :D

speakerex
09-01-2008, 11:11 AM
:) Thanks :)

ratitifb
09-01-2008, 11:21 AM
http://audioheritage.org/vbulletin/showthread.php?t=5343&highlight=2426H

http://audioheritage.csdco.com/vbulletin/showthread.php?t=700&highlight=Diaphragm+Centering

be carefull with free metal screw and screw driver so well loved by magnet strength :D

speakerex
09-02-2008, 11:46 AM
good point!