I have a couple of things that might work, depending on budget and how fussy you are 1. Red Iron Amps makes a tube preamp called the Pedal Push'r, it has a nice range from full to bright. He's a custom shop, so if you needed a different EQ or even the XLR output from the Buffer2 I'm pretty sure he could do that. All that said, it ain't gonna be cheap! 2. If you can live without tubes, the JHS Colour Box does everything you want-warm tone, clean, great EQ, XLR or 1/4" output, HPF to adjust the low end (which actually allows you to boost and cut at the same time for some very interesting low end sounds). 3. The SIB Varidrive is a nice tube pedal that can be an overdrive or a preamp. They're not currently building them, but I know a guy. Everything else I've got is 19" form factor, sorry.