PHONO PREAMP

Stay away from those phono  stage using 12au7s. High end tube gain stage should not use those cheap tubes w/ high output impudence and non-linear gain. High mu tubes may not Sound smooth as directly heated tubes, but at least be able to drive equalizer network w/o too much variance. Also, the real cost no concern phono stage should use inductors in equalizer.

Btw,atmaphere amp sucks: its output impedance is so high that only speaker has reasonable punch driven by those type of otl amps is eletrostatic speaker. Furthermore ,even after extentive mod, atmaphere amps longtail differential driver stage is too weak (guess which tube number is the dtiver tube :)).