just replaced my audio research ls-1 with a mac c2200, no comparison!!, the mac is an unbelievably great preamp..i compared it side by side with an updated/vintage audio research sp-11 and frankly, the mac was far superior, bass is exceptional with the mac preamp, very controlled and acccurate, and the rest of the sound spectrum is gorgeous, the sp-11 seemed to have a more laidback yet veiled sound...when listening to cd's i was shocked to find how good some of the older cd's can sound...as i have been primarily listening to vinyl, it was a pleasant surprise...additionally, i can not find fault with the phono stage...overall an excelllent choice for a tube pre-amp, sorry i cant compare it directly to the blue circle..hope this helps
