I've been searching the interwebs for a week and haven't found my answer yet, so here goes. I am going to be gigging with a rackmounted preamp/power amp combo (avalon vt-737sp). The preamp has 3 inputs, unbalanced 1/4 t/s, balanced mic level, and balanced line level. I would like to have the option of coming directly out of my bass with a balanced mic level signal, to minimize the poop from having a 50' unbalanced ling out on the floor. This means having an onboard DI, essentially. I'm experienced enough with instrumend wiring and audio to make this happen, if I have a schematic to at least start with. Specifically, Here's what I'm looking for; Both balanced and unbalanced lines from the instrument DI must be active, capable of taking +48v phantom power Small enough to fit in the instrument cavity of a bass with 2 pots and a 9v battery No coloration. None.