joey54207 posts05-01-2020 12:58pmAesthetix Calypso or Pallene, Audible Illusions M3 or if you can live without a remote the newest Quicksilver preamp. They all work well with the M120. You might want to reach out to John Rutan at the Audio Connection in Verona NJ. He has a lot of experience with Quicksilver.
Agree with Joey54, several preamps sound nice with them, including the underrated QS Linestage with a pair of good 12AT7 tubes. The remote version sounds good too, some prefer the non-remote version sonically. Some other members here running Aesthetix with Mono 120s with success. Dehaviland, Erhard-Audio, AI M3 all potential candidates...
I truly enjoy running an upgraded Cary SLP-98 (6SN7 based) tube preamp with my Quicksilver Mono 120s. This combo is very responsive to effective changes on input tubes and RCA interconnect changes.