Try the Placette passive risk free for 30 days and see what you think. I haven't heard it yet but everything I've read indicates this thing excels at adding nothing to the sound and provides an extraordinarily accurate volume control with remote. I'm going to try it myself since they give you 30 days--I have nothing to lose and at $1500 this could be an incredible bargain. If you're truly interested in a preamp that just passes the signal I'd say this unit is a must audition. Take a look at www.placetteaudio.com. Best of luck.
Tim
Tim