Audible Illusions vs. Audio Research?

You need to tell us your budget and whether you are willing to buy used.

Either that, or tell us which models you are looking at, so that those audiogoners (I love that word), can give you their impressions of the units they have used.

I have had the old reliable ARC LS-2 in my system for many years, and still like it. (I have the PH-3 phono preamp as well).

Good Luck in your search!

if you budget is in that same price range, pickup an Adcom GFP750 for a bargain preamp (run passive when you're not listening to rock) and active when you are.. they sell for about $700 used here. The next step would be to upgrade your CDP. Don't do buy any singlebit players.

Sand/shot fill your speaker stands, spike them if you have carpet. this will help with bass response and imaging. If you stands don't have spikes at the top, then buy some "BLUE TACK" to stick them to the stands. (this can be found at any craft store to put posters on walls without tacks or tape)

The CJ might just need tubes, but it will never be a rock and roll pre-amp.

The Audible Illusions preamps(L-1, M3A or new L-2) form a synergy with the McCormack equipment and offer excellent sound. M3A has phono, other two do not. However, the new L-2 does offer a factory phono board as an option and is remote control which the others aren't.
For the price they are offered used, they can't be beat!
The ARC Reference stuff is better for a lot more money but not that much better and in some instances, highly debatable on an individual impression to what good sound is. I'm basing this opinion on having used all of the AI stuff at some point and direct comparison to ARC. I'm sure other opinions will be along shortly.