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View Full Version : Compression driver diaphragm replacement instructions. TAD 4001 or JBL 375/2440



Lucabratsi
08-06-2017, 10:36 AM
Hello, I have a few TAD 4001 compression drivers and bought new replacement diaphragms. Does anyone have a procedure for replacing? One main question is the silver square spacers between the diaphragm and housing. Some of mine have two, one stacked on top of each other, and one has only one. Which is correct? The new diaphragms have new spacers on them. Other information like alignment, screw torque, and first testing techniques would be great. Anything similar for a JBL 375 or 2440 will also help.
Any help is greatly appreciated.
Kind Regards

Mr. Widget
08-06-2017, 04:28 PM
For original performance you will need a test bench with test mic, target curve, and additional information to determine the proper spacing between diaphragm and phase plug. I don't think torque settings are all that important, but getting the diaphragm properly centered and spaced is critical if you want "as new" performance.

There may be TAD certified repair centers, though I doubt it. Most people simply plop the new diaphragm back into the driver sweep a tone to listen for buzzing and adjust until they do not hear a buzz which will avoid gross misalignment.

The same is true for the JBLs. Every driver leaving the factory is fully tested and must pass specific tests prior to being shipped. Once a driver has been in the field or has been reconed, all bets are off. I'm not aware of anyone doing repair work with a tabletop anechoic chamber and the proper test curves to really insure proper performance.


Widget