PDA

View Full Version : Battery test for a 2425J driver ??????



jarrods
04-23-2006, 03:29 AM
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7409240377

"I am a novice when it comes to these things so I will tell you what I know about it and then it will be up to you. I was told to put a 9 volt battery to the connecters and I should hear a click, well I did and I didn't hear the click."

I thought battery checking on these was not a good thing to do???? Is that correct and why?

thanks,
Jarrod

jbl_man_uk
04-23-2006, 05:12 AM
I dont think putting any DC voltage into a HF driver is a good idea,even if it is only 9v.:(

Robh3606
04-23-2006, 09:18 AM
Generally it's not a good idea to put dc into any drivers. The applied voltage is trying to drive the coil out of the gap. The only thing holding it in is the suspension. Depending on the voltage you could easily fry the coil as it's driven away from the gap and has much less of a heat sink. 9 Volts and 4.5 ohms voice coil gives you 2 amps. 2Ax9v is 18 watts. I really don't know if a 9v battery can supply that much current but the implications are there. With a compression driver it may survive, try that with an inexpensive soft dome tweeter????? If you want to use the test stick to a 1 1/2 volt AA size. Less voltage and less current. What does this tell you about the driver??? Just about nothing. You have a working coil, and it's not jammed in the gap. I use this test to verify driver polarity on the cone drivers. I measure the DCR on the compression drivers to make sure they are in the correct range.

Rob:)

Zilch
04-23-2006, 11:17 AM
While it's unlikely the 9V battery blew the compression driver, 1.5V would have been the maximum I would have used, then only if I didn't have my trusty Fluke to measure the DCR.

What IS likely, since they didn't hear a "click," is that the diaphragm will need replacing.

In any case, the driver requires servicing....