Hattor Audio preamps?

Talking with Arek he suggested the AMRG to me. His words were they were more musical. This was in response to wanting more "body or warmth" in the setup. 

@pioneerhip 

In a different thread you asked about Hattor's Tube Active Stage and I said I would answer here in this current thread.  I have cut/pasted and slightly edited portions of a couple of my previous posts that I believe will answer your questions about the Tube Active Stage:

Active Buffers

The functional purpose of an active buffer is to improve impedance mismatches by reducing higher impedance inputs to lower impedance outputs.  This can be helpful when driving amplifiers with low input impedances, when using passive volume controls that do not actively buffer the signal, and/or when driving long interconnects.  The effect can be significant, even in cases of unity gain (i.e., no net voltage gain between input and output), and the change in sound is sometimes described as having more body, tonal color, and drive.   Active buffers can be either fully solid state or tubed.

Tube Active Stage

I use the Hattor Audio Big preamp in passive mode to control the volume of my system and it sounds significantly better to me when followed by my SMc Audio buffer (solid state and unity gain) that is based on their VRE-1 preamp.  I also have the Hattor Audio Tube Active Stage, which is a tube buffer that typically comes with 9dB gain (mine has 6dB).  It is basically a tube buffer stage without a volume control. I have tried the Tortuga Tube Buffer on one of their tours, so I had it in my system for about a week, and I also tried the Purity Audio tubed buffer in my system. 

IMO, and in my system, the Hattor Tube Active Stage sounds very good although it just doesn't provide quite the magic of my SMc Audio TLC Signature buffer, so it is currently sitting in a box.  However, if I didn't have the SMc buffer, I would be perfectly happy to substitute the Hattor after my passive volume control.  

The Hattor Big preamp also comes with an opamp active stage (mine has the NewClassD discrete opamp stage), which can be set to 3/6/9 dB gain.  I bypass the active stage to run the Hattor as a passive into the SMc buffer.   However, I have tried it through the discrete opamp stage and I also find that to be an improvement over running it passively.  Therefore, in ranking buffers (some with low gain) in my system, I would put the solid state SMc Audio buffer first and the Hattor Tube Active Stage second, both of which I would be happy to use.  Third would be the discrete NewClassD opamp stage in the Hattor Big preamp, which I would judge as just a small step below the first two, although others may reverse the order and prefer the opamp stage over the tubed stage - they are close.  Finally, I just did not like the sound of the Tortuga or the Purity Audio buffers in my system.

and, more thoughts...

As I remember it, I was impressed with the sound through the internal NewClassD op-amp active stage of Hattor’s The Big Preamp. The drive, dynamics, and clarity were very good.  My recollection is that I could live with either the tube stage or the internal op-amp stage. 

Hello everyone... I have very little experience with passive preamps... I only had a Promitheus whose sound was good but the built quality was mediocre... (RCA jacks were too small)... recently I started a conversation on audiogon in order to find a preamp that would be a good match for a GaN-Fet amp... I wonder if a passive preamp would be a good match with such an amp... anyone has experienced this combination ?

I don’t now why the normal rules wouldn’t apply - passives work best being fed a low input impedance signal (<200’ish ohms) then output to a high impedance amplifier input (>50K ohms) and being positioned so the output IC only needs to travel a short distance to the amplifier (<1.5M).

Even if you meet those guidelines, some (but not all) still find their passives lacking in tonal body and drive that active stages seem to provide.  The only passives I didn’t have that issue with were AVC types.

@ozzy62 earlier in the thread you had mentioned that you had a Don Sachs preamp; I've only heard good things about Don Sachs. I know you and @mitch2 have Aric Audio amps and Hattor preamps, but was curious if you had tried Aric's preamps. I'm a little torn between Don Sach's, Aric Audio, and Hattor for a preamp which would be matched with a Aric Audio Transcend Push Pull (preamp bypassed). Regardless of the answer, this thread has been extremely informative.