Audio Research Preamps vs. Conrad-Johnson preamps

My experience with cj and ARC is the cj had a natural warmth and smoothness of texture while still revealing music's subtle details.  In a head to head comparison I found the ARC to be cooler with the ever so slight hint of a hifi sound.  The fact that I was listening through imperfect electronics was a tad more revealed through the ARC gear.
Elizabeth's comment about the differences between vintage cj and new production is spot on.  Anyone who had exposure, for example, to the cj PV5 or 10 will likely remember the "honey-like" sound of those models.  I never heard that from any ARC gear vintage or otherwise.

Try to find a loaner Atma-Sphere MP-3. 

Change the stock tubes to Black Treasure and then compare to the above 2 you are looking at. You would be very surprised!

I am also interested in adding a preamp of one of these brands in my system. Especially sp16/ls16 or sp17/ls17 from AR or pv14 or pv15 from CJ. My speakers are Martin Logan requests and power amp is Aragon 4004. Any input would be highly appreciated. Thanks.

I have had, in order, a CJ pv1, a five, and a 9a. The 9 has a very fine phono preamp section. It requires a MM or homc, which is what I used.

I had an ARC SP 8 for some years too. As others mentioned, it has a more analytical sound, but still very satisfying. I know this is vintage stuff so it might not be very helpful.

 

Audio Research and CJ use different tube lineups, which accounts for most of the sonic difference. You might prefer 6DJ8 vs 12AU7, which have very different distortion spectra.