[quote name='flyfisher' post='1305134' date='Jul 15 2011, 08:31 PM']I've never had an active bass, so I'm just thinking out loud really, but why can't such things be phantom-powered like many microphones?[/quote]
I think some are, although I've never seen one, and I've never seen an amp with a powered XLR or TRS input either for that matter.
I suppose the consensus was that it's easier to deal with replacing the odd battery than supplying power down a cable.