Call me crazy but I'm not running a high pass filter on my DS21 with an inuke 3k bridged to it. I don't think the driver can be bottomed out. I think Data-bass confirmed this but not 100% sure. As the voice coil moves farther out of the gap, the motor has less power over it, which along with the restrictions from the suspension creates a situation where the cone simply cannot move far enough to crush the former. It will however probably sound like crap flopping around at 10hz.