Electrostatic Speakers/SS amp - what tube preamp?

On Audiogon: Rogue 99 magnum for $1500 or Cary 88 for $1200 would be your best choices. If you're looking at an AE-3, from experience, the DJH version is a big step up.

Considering your use of a balanced DC coupled solid state amp with an input impedance of about 50 Ohms(?), I think the the well built, user friendly, flexible, balanced, low out put impedance, DC coupled, neutral sounding, Sonic Frontiers Line series make ideal candidates.

I will second the SF choice.The SFL-2 is much better than the SFL-1{not sure where Sig.version comes in}.Possibly,the terra Song SS-1 or Marsh P2000.Are you using digital or analog.Digital always sounded better using this amp than did my 46K analog set-up.You will want something with a little sparkle up-top.

I will third the SF recommendation.

Gilbert Yeung at Blue Circle loves Martin Logans, and uses a pair of Odessey and a pair of CLS (amount some other brands) to tweek and test his designs.

His pair of CLS are pink (a custom job just for him by Martin Logan as a joke).

So put his tube preamps on your list. The matching amp to his BC21 and BC21.1 preamps is a solid state amp (BC22). Many also use his BC3 preamp with either a BC22 or a BC26.