ARC users please

I have been trying many different budget preamps just for the fun of it. I have stumbled upon a Audio Research SP7.
This thing sounds amazing. Any preamp under $1000.00 that I put in my system doesn't come close to the sound of the SP7.
Everything else I try sounds like it is in mono compared to the SP7. I don't know how to describe the difference. The sound is more alive and every instrument is in place.
My question, is this a signiture ARC sound ?
I have read good and bad reviews of the LS3. So I am not sure if I need to look for a certain model to upgrade to, but still keep that synergy in my system that I have now.
Thanks, Scott