Looking for an incredibly dynamic preamplifier

Dave Davenport's design would fit your bill; if you are willing to get your hands dirty and build one. It's a differential parallel feed design (the bias current and the audio signal share only one devise, a 6N1P triode). It's tranfomer coupled on both the input and the output using the excellent Lundahl amorphous core trannies. The input transformer does the phase splitting chores for the differential gain stage. I don't know if you are aware of the fact that most op amps used for the input chores on balanced amps and preamps have a rather low CMRR (common mode rejection ratio). Transformers have a high CMRRs; plus they provide absolute galvanic isolation between your sources and your amps (ground loops are NOT an issue). I have this preamp design in my system. It is dead quiet, very dynamic and very musical. It's also driving two tube amps (input Z 100k and 500k) and one SS subwoofer amp (input Z 50k) with no problems. This preamp was written up in AudioXpress if you have access to past issues.

The most dynamic preamp which I have heard is the First Sound Presence Deluxe. However, in order to hear it at it's most dynamic your choice of tubes is important. The Siemens 6922, in my opinion, brings out the dynamics the most. A little less dynamic, but also less ragged in this pre is the Siemens 7308, which makes this a world-class linestage. The F.S. has a solid bass, but, in my system, not extremely deep and, in my opinion, lacks the iron-fisted grip that you talk about. However, it does have an extremely transparent midrange which makes female vocal and horn listening very exciting and even sometines breathtaking. In the right system, with the right recordings, the vocalist can appear as if she is in your room singing to you. Great soundstage and separation of instruments. Unlike the CAT described below, no sweetness here, but still, due to the transparence, a very engaging sound.

Slightly less dynamic, but with deeper and more iron-fisted bass is the CAT SL-1 Ultimate. I think if you like the rock-solid, powerful deep bass, you should listen to a CAT. From the lower mid on up, the sound is sweet, smooth and musical, rather than hiper-detailed. The music is all there, but not in the super-transparent manner that the First Sound presents. Great musicality, lush but not syrupy sound, wide soundstage, but doesn't have the near-pinpoint imaging of the F.S. The imaging here is more diffuse than the F.S., but as an integrated whole, this unit is also exceptional.

I have not heard the Wytech or the Placette, but have heard the stock Aesthetix Callisto Mk I. I thought this unit in the system in which I auditioned it specifically to be lacking in dynamics. Just my opinion.

I do own both the F.S. Presence Deluxe Mk II 4.0 and the CAT SL-1 Ultimate Mk I.

You may want to check out the Lamm L2 preamp. This preamp provides a very high level of dynamics and detail and presents it in a very natural way.

The deHavilland Ultraverve preamp is wonderful

Rayhall, Thank you for your help. The First Sound products appear to be ultra-transparent, very dynamic, extremely quiet, and have good bass (but not extremely deep). These are obviously great qualities but I wonder what the trade-offs are. The qualities put me in mind of Nordost cabling (which have these admirable qualities) but, which I generally dislike because of *what I perceive* as a lack of high frequency information and poor portrayal of spacial qualities.
I'm obviously going to have to go and listen to the First Sound products to make up my own mind, but (since this is what we do here) can I please ask...
Does your First Sound linestage have excellent high frequency extension?
Does it "energize" your whole listening room and regularly project images well in front of the speaker plane when the recording calls for it? When images "speak" does their voice have good "action", in other words, does their voice project from the image and wash over the listener? What I'm getting at is: Are you the listener "inside" the music or are you left "watching" the music as if watching ghosts in another dimension behind an invisible, yet impenitrable plane?
Thanks again.