Summary:
in the past 4 months, i have listened to almost every single 'reference' preamp out on the market. I had a Mark Levinson 380s for years. It did a fine job. But in order to get a more musically rich sound from my ML 33H and Sonus Faber Amati setup, I began to look for a better preamp.
It was only natural to consider the ML No.32. It is certainly one of the most evolved and refined solid state preamps I have ever listened to. It almost sounds more tubey then the Audio Research Reference Two which I also auditioned.
Between the No.32 and Reference Two, I would have picked the No.32. The tonal richness is impressive, and the bass (or rather, the foundation of sound) seems to be so much better. The Reference Two was excellent at holographic imaging, but the 32 is probably even better. Hard to tell.
But I then listened to the Audio Note M6, which was VERY impressive. SO MUSICAL and rich. But!!! No remote. I am a 'modern' man! I want a remote control! I think having the ability to remotely control the exact volume! It's crucial!
So my search for the ultimate preamp continued. And that's when I listened to the Conrad Johnson ART!
Music! nothing but musical sound! It sounds richer then the 32, but no 'heaviness' like the M6. The sound is just right. Soundstage, tonal richess, dynamics! (micro and macro)... it was simply 'true' to the source. the ART is a real masterpiece.

Strengths:
pure music

Summary:
My system progressed from Mark Levinson 38s to 380s to Audio Research Ref One and each time improvements were noticable if not earth shattering. The Ref One was without doubt a significant step forward and I dwelled in audio nirvana for a couple of years.
Unfortunately a local dealer brought the Conrad Johnson Art to my house just to listen - no pressure to buy - just listen. Good heavens - it simply trounced all aspects of the Ref One. The Ref One was reinstalled - soundstage collapsed detail reduced. The sound was veiled and (for want of a better description) dull. I could not believe it. The Art was reconnected - HEAVEN. But oh the price and after promising myself the Ref One would remain in my system for years. I had to buy it. It is without doubt an incredible engineering feat.

RATING Well it should get a ten but with only 5 stars what can I do but give it 5 stars. I doubt very much that this preamp has an equal. Congratulations Conrad Johnson.