Valve phono stage

I bought a used Aesthetix Io mk2 for about $3800 years ago, and later upgraded. To my ears it sounds better than e g the Steelhead, ARC PH6 and others I've heard. Especially after I upgraded to dual power supplies and partial eclipse status. You have to accept some tube noise, but with the latest quiet stock tubes recommended by Aesthetix it runs more quiet than before and it is not much of a problem with a cartridge giving 0.3 or more mV output. The main issue is to get ultra-quiet tubes in the very demanding first gain stage. Maybe, it can tackle 0.2 SL types of carts also. A step-up transformer is not recommended. It only has MC inputs (one XLR, one RCA). It is not fully balanced, but the balanced output is clearly better than the single ended output. So to get the best of it, you need a balanced preamp (and - ideally - amp).  Regarding the input, from the cartridge, Aesthetix tells me opinions vary, but often, customers prefer single-ended (RCA) input. I use a DIN-RCA Kimber KCAG cable, and have never had hum problems. If you go the Io route, eventually starting with a Rhea, I don't think you'll regret it. But be prepared, this is a "purist" solution.

@lewm  - is the Aesthetix Io balanced - sorry for late answer, I only saw your question now. Quote from the manual p 8:
"The phono stage contains three main amplification sections and an output buffer section. The first section is a high gain, low noise, zero feedback single ended amplifier composed of two low-noise 12AX7 vacuum tubes. This then feeds a high gain, low noise differential amplifier (two 12AX7 vacuum tubes) which amplifies the signal and produces a complementary minus phase signal. Thus, the unit is balanced from the second amplification section through the output. The signal is then applied to the third amplification section which is nearly identical to the second. It also contains two 12AX7 vacuum tubes. The filter is next in the signal path, a purely passive design with the highest grade capacitors and non-inductive wirewound resistors throughout. Lastly, the signal is buffered and sent to the output jacks in balanced form." So well, it is mostly balanced but not fully, since the first gain stage is single ended. Whatever the case it sounds great. I know Raul doesn't like tubes in phono stages and I recognize the problems, but to my ears, this is the best choice.