I received my ZU Definition Pros in late June and set them up with what I had on hand. For those who don't know, the Pros are biamped without an internal amp or XO. So I used my RWA Clari-T on top and my Pass Aleph 30 for the woofers. Between these amps is the ZU supplied Rane PEQ 55. The results were quite good, in fact quite spectacular but I had read enough about the limitations of the Clari-T which I liked so much that the notion of trying something else lingered as it always does once you've had a piece of equipment beyond the break-in point. When I heard about Vinnie's Signature 30, first from him, and then from Srajan, I got the itch and ordered one within a week. It arrived yesterday.
Just like everyone else whose comments I've read, I must say it sounded great immediately. Disarmingly great.
And this morning it sounds better. I'll spare you the audiophile terminology because it has been blunted by repitition and because I've never been able to use it well. I would say that the Sig 30 is uncommonly articulate and wondrously emphatic. Every click, tap, note, roll, trill, hiccup, ahem, and pause is delicately, deliberately and decidedly presented. Just the facts, Ma'am. The background is absent and the foreground is transparent. I cannot believe this simple little black box can be the reason that Jesse Winchester dropped by this morning. And then, at the request of my teenage son, Deep Purple took a minute to perform "Smoke on the Water" as never before. The experience contradicts a lot of what you think you know.
I think Vinnie moved from Massachusetts to Connecticutt to avoid witchcraft proceedings. It is clear he has struck a deal with the devil. No human could devise such an incredible and miraculous black box without the aid from supernatural forces.
The Sig 30 has only one input so I use a Purest Audio Systems passive pre as a switch box. It has dual volume controls which can be used for balance adjustments and 4 inputs which are individually accessed via toggle switches.
To address the original post, I would recommend the Sig 30/Zu Def combo without any reservation whatsoever based on my brief experience. Mine is surely a keeper. I have not tried to use a preamp with mine but I recall Srajan and a couple of posters saying that the insertion of an active pre did not improve and may have hindered the sound. The Dodd may be different. I'm not familiar with it. If it has enough inputs and can be used passively, then maybe you'll use it like I use the Purest.