Balanced preamp tube for Magnepan 3.6 or 20.1

Hi, I had that exact combination (MG 20.1's;Bat VK31SE; MC501's) and while it sounded good, it got better when I put in a McIntosh C500t (I found it used, for less $$). I am a huge McIntosh fan, but I did not think the MC501's did as well with the 20.1's. If you have the Mc402 you could bi-amp the Maggies which makes a big difference. I hear that the McIntosh C2300 is an excellent Pre-amp and it has 3 sets of balanced outs to help bi-amp. Hope this is helpful.

ARC Ref 3 or Cary SLP05, both will work extremely well. Giving you a very open soundstage and excellent bass. I think that Cary is slightly warmer than the ARC. I have never heard the BAT's or VTL's.

I have the 3.6R's and have tried both the 501's and the 402 Mac's and never gotten good results. They are great amps which sound fantastic with other speakers, and I am not sure why, but they sounded muddled and weak with my system(s). I love the Cary MB500's that I have, and I have tried many amps with my Maggies. Then probably the Sanders Sound ESL amps (formerly Innersound). VTL amps sound sublime too. I love the previous generation of them, especially the aesthtics.

Isn't this about Preamps?
I use a Modwright 36.5.

Thanks to all for your help. I'm reading all your messages to understand well what I have to do!
thanks a lot
Andrea