A lot of guys do this with Rickenbacker basses because they have a stereo output. This is what Geddy Lee did too, except his setup was all tube. He used a Rickenbacker 4001, with the stereo outs, and the neck pickup went to an Ampeg SVT for a nice tight low bass, and the bridge went to a cranked Sunn 2000S, for a distorted tube sound. If you wire up your bass with a stereo output, you can do it with the Sunn with no mods to it. If you want to go with whatever mono setup is on your bass, then you could still do it if you use a splitter coming out of your bass and run a send to each amp in your rig.