I use a solid state ARC LS3 played through the "direct" inputs which, I believe, bypasses everyting except the volumn control. This gives a fairly grain and haze free sound with good dynamics and minimal color. Maybe you could find a LS3B, which added XLR outputs or a LS2, which is similar, but adds one whole vaccume tube. The LS3 was a Stereophyle Class A component and went toe to toe with pres costing 3 or 4x more. imo, the REF series would probably be a waste of money for that amp. The amp is great, but not in the same $$$ range as the REF products, again, jmo. Any ARC preamp will be a big step up from most other brands.