I'm currently using a PreSonus FireBox for an interface and I'd like to try my hand in building some basic outboard preamps for my dynamic mics. Opamps work fine, no need for tubes. I would like (but not necessary) one design that is relatively transparent and one that is more of a 'vintage' or coloring preamp. I'll probably tweak the circuits, add things, change things anyway, so I'm looking for a nice base for that. I'm undecided as to whether or not I want phantom power, but I would only use it when taking DI recordings of guitar because I use phantom power to power my DI box. Thoughts? I've found a few simple designs, but like I said I'd like a recommendation because I don't know what designs are worth the time and money put in or not. Really just considering if it's worth it at this point.