I designed that preamp for little breakup so it should work for bass as well. Like max mentioned, can you take out the signal from the dumbleator and feed it into that ampeg? I'd try to feed it into the PI directly or maybe one gain stage before. Have fun!
My rig is a diy alembic and a QSC power amp. Imo, it's warm and it only weighs about 25 lbs for several hundred watts. If I wanted some dirt, I think I'd buy a Sans Amp DI...ymmv. For a cab, I cloned an Aguilar GS112 without a horn.
I like my own amp but I have an old Fender Bassman 135 for my experimentations so I'll use that one as a base for adding the dumble style preamp. Will keep you updated!!!!!
