Audio Research pre-amps?

Hello,

I have an Audio Research LS-3 pre-amp paired with McIntosh MC60 mono-blocks. I use an NAD 546BEE CD player and have Nola Boxer speakers on Skylan stands filled with floor dry. The cables are Kimber Heros and 4PRs...and I just added a REL T7 subwoofer.

Anyhoo...my latest thinking is that the system is a just a touch too bright...not much-just a little.

So my question is: I'd like to stick with an ARC pre-amp. Is there a model I should look for that might be a touch warmer? Maybe a tube version? Nothing too new and under $2000..$2500?

Thanks much,
Aaron