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ngccglp
08-22-2008, 06:42 PM
ok

ngccglp
08-23-2008, 07:30 AM
Hi,

Calling 4430 owners. I noticed the 4430 is negative convention i.e. when pos voltage is applied to red terminal, the woofer move inwards. Is this correct or do I need to reverse the connection?

Also, if indeed that is the correct convention, should I reverse the connection at the amps since all other equipment is supposed to create a compression sound wave when positive voltage is applied.

Thanks

grumpy
08-23-2008, 01:30 PM
should I reverse the connection at the amps since all other equipment is supposed to create a compression sound wave when positive voltage is applied.Your call. Unless you have info about each recording played, the proper
absolute phase for each one (if there is one), and keep track of this,
(as well as if any of your playback devices or other in-line amplification
maintains or inverts phase) my feeling is that this concern is much ado
about nothing.

This has become a religious war in other circles, but if a concern to you
(which I have no issue with), ensure your speaker is setup as intended
with respect to individual driver phases, and get a preamp that has an
"invert" function ... much simpler than swapping speaker cable polarity
for each song/album.

My 4430's are setup with the 2235's pulling -in- with a positive DC voltage
on the external red terminal (relative to the black terminal),
as I believe should be expected:

http://www.jblpro.com/pub/technote/tn_v1n12b.pdf
http://www.jblproservice.com/pdf/Studio%20Monitor%20Series/4430LR.pdf
:cheers:

ngccglp
08-23-2008, 02:09 PM
Thanks Grumpy, this is exactly the info I needed.