View Full Version : Re wire JBL Sub Control SB1 Question

06-06-2012, 08:21 AM
Hello all....
I have an older sub, a JBL Control SB1 it is currently set up for 4ohm.
I need to re wire this for 8 ohm and is this possible,? and any diagrams how to?
The problem is I have JBL 4401's 8ohm for left and rights, and the JBL sub is 4 ohm.
Would I hurt any thing connecting the outs from the sub to the speakers?
I am using a separate power amp for the power.
Any thoughts?

Thank you

06-06-2012, 08:57 AM
It would probably work fairly well with no mods.
It would be simpler to adjust the two capacitor values
inside the SB-1 (one 300uF cap per channel), if the overlap
bothers you. Google for the SB1 tech/spec page.

06-07-2012, 07:05 AM
What would replacing the caps do?


06-07-2012, 08:24 AM
It would move the high-pass crossover back to where it was intended when used with
4 ohm main speakers ("Control 1" vs the 8 ohm units you were proposing to use with the sub).

The crossover frequency is dependent on the combination of the capacitors I spoke
of, and the impedance of the speaker that it's feeding.

With just a single capacitor providing the crossover function, the roll off slope
is rather gentle, making the exact crossover frequency a little less critical...
which is why I suggested you might be fine listening to the system without any
mods at all, or experimenting later.

06-07-2012, 09:10 AM
Thank you for the information!
Much appreciated!