Parallel resistor on woofer (JBL L-112 Century II)

[presscot]

Here are the schematics of JBL L-112 Century II. Could anyone please tell me what is the duty of a 51-ohm resistor in the woofer section?

 

[ericj]

In parallel with the nominal impedance of the LF driver at 8 ohms, it forms a nominal impedance of about 6.9 ohms.

It does two things in terms of the crossover network filtering.

If you apply kirchhoff's current law, a fraction of the signal that makes it through L1 will be burned off as heat in R1 which decreases the output in the LF

It also changes the (3db) crossover point for the LF driver from about 510hz to about 440hz.

 

[rothwellaudio]

The woofer's voice coil will have some inductance. Placing a resistor in parallel with it makes it look a bit more like a resistor and limits the rise in impedance at higher frequencies. It will help to roll off the higher frequencies which the woofer shouldn't be reproducing.

 

[chickenwatt]

The woofer's voice coil will have some inductance. Placing a resistor in parallel with it makes it look a bit more like a resistor and limits the rise in impedance at higher frequencies. It will help to roll off the higher frequencies which the woofer shouldn't be reproducing.

I agree with your answer, but not agree with the answer of ericj

 

[rothwellaudio]

I agree with your answer, but not agree with the answer of ericj

The two answers are saying pretty much the same thing.

 

[roxoncontac]

Both of those answers were complimentary to each other. Disagreeing with one and only one is cognitive dissonance.

 

[ctjetta]

Both of those answers were complimentary to each other. Disagreeing with one and only one is cognitive dissonance.

Whoooaa, deeeep.