The last conversation I had with several Polkies was about passive pre's and the synergy needed to get them to perform with great dynamics and both frequency extremes.
Last night I decided to try out my ASL autoformer passive into my current set up. My AZ Amp-2 are extremely sensitive at their inputs. The slightest amount of noise (from upstream components) that won't show up with other amps can clearly be heard on the AZ. Also, could be that the entire signal path in the amp is less than 4" or 2.5" (can't remember exactly).
My dealer kept telling me that a passive is the most ideal for the AZ, but I guess I was having too much of a blast with another active pre and haven't really played with the passive in a while. Makes perfect sense. That combo provides the most simple and shortest signal path. I was worried my RT1000's wouldn't be sensitive enough, but OMG!!! This combo is absolutely stunning. Sounds like the soundstage got pushed back several more feet, no loss in dynamics or HF and LF. Background became noticably darker. Images are more stable and there is an increase in smoothness or "flow" of the music. The images are also larger now, in fact, quite big compared to running my active. Any hint of harshness that was present before has been completely eliminated. Hearing those tri-laminate tweeters do their thing is something I've never grown tired of since I got into Polk 11 years ago.
Man, when the synergy is right with a passive pre, it's quite a trip! So who else in here use a passive?