Thanks hammer, however i already have two f1-x’s. I had them in a rack with my sf-2, ds5 and power amp but i only tried bi amping a couple of times so i moved one of the the f1-x’s into a smaller 3u shallow rack with another Ds5-r and 1u power amp. This small rack is the one where i want to swap out the f1-x for another Sf-2 so i still have a more lightweight and tonally more versatile preamp than the f1x to take when travelling light.