I play electric bass with the band i am in, and i just got an upright. I want to play the urb on some songs, and the ebg on other songs. It would be very expensive and inconvenient to have a eb rig AND an urb rig on stage at the same time. I was curious, if i have some very transparent speaker cabs(bag end, ea, epi, etc.) and the bass guitar head of choice, could i plug my upright pickup plus preamp directly into the effects loop return jack as it is a power amp direct input and use the onboard tone controls to eq my sound?