Hmmmm. I’m now on the horns of a dilemma. As enlightening as the mixer route info is (seriously cheers @EBS_freak) it is useful in another way as in to hone my nebulous ideas about what I want/need between my bass and the QSC. I will further discuss the live mixer route with my duo partner and no doubt come back here for further info. What worries me about the mixer route is it means (or at least will for me) a lot of learning new stuff, which, of course, isn’t a bad thing but a) I’m not particularly tech minded and b) I’m trying to keep the kit as small as possible.
I have read up on the Grace Designs Felix which appears to have two channels with separate EQs, as does the Bassbone OD (thanks @Muzz). I’m also not averse to the idea of having two preamps and switching between them with something like the Boss LS-2, but again it’s not the ‘one box solution’ which brings me then back to @EBS_freak‘s mixer solutions. I suppose I’m thinking more of when I’m at home noodling/writing I just want a very simple set up but one where I can swap basses quickly (thinking about it that applies to live too). I asked the initial question because I hoped there was such a thing as a two channel preamp that could drive the QSC and cope with inputs from a passive electric bass and an active acoustic. I think I’m worried that if I went down the mixer route I’d barely use a fraction of its capabilities but then they are there when possibly needed in the future (and once I’ve learned the difference between an XLR and a barometer). Then there’s cost, the Felix is around £1100 and does a very specific job, albeit brilliantly apparently, then the mixers cost much less but do loads more, but are bigger, more complicated, bloody cables everywhere...
Not so much the horns of a dilemma but the antlers maybe, anyway, as always, everyone thanks for the input.