RCM Sensore Prelude OR Zesto Andros PS1 Phono?

Well, you're talking apples and oranges. The RCM is a solid state while the Andros is a tube preamp so I'm not sure how meaningful any comparison would be outside of your system. Is the rest of your system tubes or ss? What cartridge will you be using?

I happen to own the new version of the RCM (the Furutech version) and in my otherwise all tube system the RCM sounds very clean, very transparent, neutral, and dynamic. But you already know that since you're familiar with this product.

The Andros is also quite a bit more expensive so you need to take that into consideration as well unless it's not a factor. From what I've heard about the Andros, it sounds like you can't go wrong with either unit, all else being equal.

What cartridge would you be using?
And am I understanding correctly that you already have the Prelude?

I see. Sounds like you've assembled a very nice system. Congratulations. I'm not familiar with the ZYX cart, but both preamps should work fine with it. Why not stick with the Prelude since you're already getting it and you liked it in other systems? If you don't get to know the sound of your system with the Prelude in it, you won't be able to determine whether any upgrade actually makes an improvement. My two cents.

Mordante,

The fuses and terminals are all Furutech. I spoke with Roger Adamek (RCM owner and designer) and the difference in his opinion is not subtle as compared to the original Sensor, which is a great unit in its own right. I had the benefit of speaking Polish with him as I grew up there and he is a very nice man, as most of the designers I've spoken with are.

If you want to ask anything more specific, feel free to email me at actusreus13@hotmail.com