I already had the hotel RB-1590 amp and finally found a reasonable deal on an RC-1590 preamp, which replaced my RC-1580. I was going to go to vinyl, for which the 1580 was designed. But, I decided to go all digital instead. With the 1590 pre/amp combination, the separation and soundstage are very good to my ears. Some have said that the RC-1590 sounds a "a little thin." I am not sure I would disagree. But, if it does sound thin, it is only very little so. On the other hand, this combination is one of the few I have had that I can listen to for many hours without feeling fatigue. The dynamics are very good. I have had combinations with the RB-1590 that sounded more dynamic. But, I could not stand them for more than about 30 minutes. So far, especially for the money I could afford, I am very pleased indeed with this combination. I no longer feel that my preamp is the limiting factor in SQ. I have some XLR cables coming, and I expect them to give me "thicker" sound. But, even if they don’t, I don’t feel the need for more. It sounds as good or better than most systems I have heard at quality shops, with less fatigue. Once you get to a certain level of SQ, the benefit/cost ratio seems to get smaller and smaller.