I heard from a reputable source at ARC that the Ref 5 will have the same tube compliment as the ref 3. Totally new circuit boards with some circuit changes. The board is horizontal instead of vertical. The sound improvement is said to be quite substantial. Deeper, more articulate bass and more extended top end is probably the first thing you will notice, but this improvement is across the whole spectrum. There is an additional finish combo with silver knobs/handles with the natural finish. I'm sure it will sound amazing, I just placed my order and delivery is about 4 weeks out. I'll let you know more when it comes in.
