Thank you for all the responses. I'm aware that the resistor wasn't the cause but the symptom. And it's not really a servo sub like the HGS. It doesn't have a sensor connected to the subs VC. I was told Velodyne will only let authorized service tech's have the schematics. As of now I am running an external amp.
That is true that it does not have a VC sensor, but it still has active EQ. All sealed subs need some type of EQ or they have a very high F3.
This is the arrangement of your sub.
[The CT series has four models
: CT-80, CT-100, CT-120, and CT-150, with the respective drivers 8", 10", 12", and 15" in diameter. The CT-150 has a 250 watt rms A/B amplifier with current sensing feedback from the driver voice coil (2 1/2"). Velodyne's top of the line subs use a solid state accelerometer mounted on the voice coil. Current sensing feedback is less accurate than servos, but it is also less expensive. Current sensing feedback works by knowing what the current is that is being fed to the voice coil by the amplifier, and sensing what the current is that is being generated by the actual voice coil movement within the gap of the magnet. The difference in the waveforms between the amplifier feed and the voice coil generated current (this difference represents distortion) is inverted and fed back into the amplifier. This cancels out much of the distortion produced by inaccurate movement of the driver cone. The CT-150 is the only member of the CT series that has current sensing feedback.]
With current sensing that sub has an f3 of 23 Hz, so very good bass extension. I would estimate that with your current external amp set up the f3 is at least an octave higher probably mid forties.
So unfortunately you don't have the same sub you had before.
I would guess that if you equalized it with something like mini DSP by boosting 12 db per octave below about 45 to 50 Hz you would have performance in the ball park of what you had before.
You would need a 12 db per octave filter at 25 Hz to prevent driver damage. I suspect that current sensing system also prevented excessive cone excursion.
