The preamp is just a couple of ounces. The two 9-volt batteries are heavier.
What really adds weight to the basses is the high-mass bridge and a set of dual coils. Between those three things on a 5er or 6er I believe you are talking about 3 pounds easy...
J
makes sense. admittedly, part of my thinking on this was the old haz lab preamps, which are probably way clunkier/heavier.
that being said, if you're worried about the difference between 9.9 and 10.2 pounds, a preamp could tip the scales, no?