What qualities stand out in really good solid state preamps?

@jc4659 "2-dimensional versus 3-dimensional images" -- well said.
Good info about the the different Ayre models.

@yyzsantabarbara 
"My goal is to let the preamp produce the sound of the amp, source, and cables without adding to the mix" -- that came through very clearly in your first post, too. Got it, and the additional warmth in other equipment provides the rationale. Too much of a good thing is too much. My buddy has a lot of character in his Coincident Dragons with 300B tubes and so he wants a passive pre ahead of it. This approach makes sense.

@ghdprentice 

I'm a tube preamp lover, for sure. But as was said above, sometimes it's nice to hear what the rest of the chain is doing, minus the preamp. I like swapping gear in and out and listening for differences. I'm not converging on one preamp, amp but want the chance to keep mixing things up.

@robshaw 
Thanks for the Benchmark shout out.

@hilde45 your question is 

What attributes do you look for in a good solid state preamp?

for me it is the following - 

• tone - must be natural 
• dynamic range - must be able to sound laid back and gentle but scale up to explosive forces fast, as fast as demanded by the recording 
• low noise floor
• Texture in the bass
• warm and palpable mids
• extended and sweet highs
• nice, non-clicking silent volume control (want to be able to adjust volume without hearing any clicking or other artifacts)
• must image well and create a realistic and colorful soundstage

I don’t care for studio monitoring matter of fact in your face presentation 

There is a Neurochrome 686 for sale at present in the US.

I know this Amp's capabilities very well, through being demo'd it in the UK in various build guises.

The 686 I have heard in use on a £200K System compared to the best part of a £50K Soulution Power Amp, with a Solution Pre Amp used for both Amp's demo's.

The 686 being approx' 25 x cheaper was a real contender, and I mean real contender. This is what can be had when the design for the Power Amp has a Parts List that is between £2K - £3K.

Both these Amp's used in the system and environment that was set up for the system was the best SS Power Amp's I have heard in use to date. 

@soix   +1 

Not so secondary issues would be warrantee and serviceability. Bryston excels here, at the expense of the last iota of performance. IMO

@hilde45 

Have you ever considered a hybrid preamp?  I just bought a PS Audio BHK Signature preamp and it has a couple of 12au7’s for the input and mosfet’s for the output. Only had it a couple of days, but I am really enjoying it so far.