Hi griller,
I tell you, what I landed on so far might seem a bit odd. The sub is at '0' phase shift, stock roll off and somewhere between 1/4 and 1/3 volume. I do not have the cross over's in the system and have the sub crossed over at approximately 70 hz. This has so far enabled me to hear the Emeralds full out with the sub only helping out with very low notes and overtones.
Of course it is tempting to crank it and listen to the sub once in a while because it is cool. However, this setup seems to work at my volume levels (relatively low) and when I switch between different types of recordings or bump the volume I don't have to adjust it.
I would be interested in your experiences as well.
DR