Adding Series Resistance to Woofers . . .

Steve_Lee

I know it is generally regarded as poor practice to do so but I notice SOME PEOPLE [around here] adding 1/2 an Ohm or more in series to their woofers.

After playing around with this additional resistance (1.0 Ohms) applied to woofers in WinISD I noticed:

1. Happy boost/peak in the drivers FR on the low-end (right where the "slap/punch" frequencies reside
2. Slight reduction in bandwidth at each end of its FR range
3. Smoother/slightly steeper roll-off on the high end
4. Reduction in GD for BR alignments (Ported/Vented)
5. Increased GD for sealed/closed-box alignments
6. Reduction in Qtc (sealed/closed box - tighter/cleaner bass)
7. Flatter over-all FR between potential XO points
8. Reduction in Port Velocity (for BR/Ported alignments)
9. Increase in cone excursion for the same power (W) applied
10. Significant reduction in F3
11. Increased Port Gain for BR/Ported alignments

Then, (inside my skull) these things became rather useful --> https://meniscusaudio.com/product/twisted-zisters-1-0-ohm-35-watt-power-resistor/

(Parallel them to gain power handling for fun and profit)

Questions: ??

What negative effects might the addition of series resistance have aside from reducing electrical efficiency, heating up a resistor, kids starting a fire while the parents are out of town due to SPL demands of the amp, dropping the voltage and all the usual/obvious nasties.

How about distortion? is it increased or unnoticeable?

Any other thoughts for or against?

jr@mac

I add series resistance in modeling to approximate inductors. Everyone should do the same. I don't actually add a resistor, but have been tempted before. I have used air core coils with high DCR in the past, to hit certain modeling goals.

For the type of resistor you linked, they need a proper heatsink to dissipate their rated power.

Wolf

Ditto.