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Flemming Skov
12-10-2005, 06:10 AM
Hi,

When JBL say's Re = 8.8 ohm and Le = 2.2 mH does it mean that the impedances develop like Z=Re+jwL or is it Z=Re//jwL ?

Need it for crossover calculations!

Regards
Flemming

duaneage
12-10-2005, 07:56 AM
Re usually is specified as a DC measurement of voil coil resistance and the same usually goes for Le, the voice coil inductance at DC. For calculating Zobels this should be sufficient and if you flatten the impedance curve first you should be able to get an even 8 ohms across the board.


I would measure the impedance at the crossover frequency after applying a Zobel rather than rely to much on published data.
my .02 , thats all.

Robh3606
12-10-2005, 08:48 AM
"Le, the voice coil inductance at DC."

What we are interested in is an AC measurement typically measured at 1KHz for woofers.

Rob:)