Velo62, I have owned both the AR LS-25mkII and the CAT Ultimate II at the same time and was able to give a just audition with both before choosing which preamp I would keep.To my ears and in my system the AR was extremely detailed throughout the scale, but was also extremely sterile sounding almost as if a veil was covering the music from coming into bloom. The CAT on the other hand is extremely revealing (A/B compared with stock tubes)and over all sonically preferred. Top extension was very good, bottom was solid and mids were detailed, but not as much as I would like. This now resides with my system, and it wasn't until I rolled tubes that I found the CAT performing much better. Get rid of the Sovtek tubes without question IMO. Hope this helps.
Tube preamp suggestions.
I enjoy a lush sound with extended decays, bass with weight, and holographic mids. PRAT, speed, and resolution are not my top prioroties. Looking for a preamp that will compliment my vintage Mcintosh MC275 ( decked out to my tastes with gold lions and telefunkens ) amp and bring digital closer to analogue. Not interested in 6h30 tubes, tried cary slp98, bat and AR ls25 mk2...I seem to prefer the 6922 based versions. Associated gear is Focus Audio FS-88 speakers, using Harmonix interconnects & powercords and nordost SPM cables. I already have dedicated lines and using wattgate outlets with no power conditioners. I really enjoyed the Supratek Shyrah but found it very microphonic, couldnt get within 15 feet of it with a cell phone. Im interested in Emotive preamps and Blue circle but no dealers remotly close to my area. Any opinions on these 2 or or suggestions would be appreciated.