What qualities stand out in really good solid state preamps?

@soix Ditto!  👍👍

Audionet makes the best preamps in solid state I heard full stop!

Mola Mola good too.

@soix I never said I knew better than anyone else, you did. I never said my statements were objective fact, you did. I made a point of saying everyone has their preferences and prefer different gear. And objective fact is what exactly? Some people on this forum downplay the value of testing equipment using measurement gear. I can understand that, as measurements don’t tell the whole story in my experience. My ears are my reference measuring device. So what is objective fact? In listening to music it’s mostly subjective I think. 
 

You’re right that I don’t know exactly what the original recording sounds like. I wasn’t in the studio or at the venue. But I do know what a piano should sound like. i’ve played one for decades. It’s why I listen to solo piano recordings and solo acoustic guitar recordings, as I know what those instruments sound like quite well, Yes my piano in my room sounds somewhat different from another piano in a different room. But it is the best frame of reference I can have to know if a piece of gear sounds true. The OP uses a violin to evaluate gear for the same reason. Perhaps I should have said that a simplistic view of neutral is that the gear is true  the sound of the instruments. 
 

When I audition gear I use recordings I know well that I find to be true to the sounds of the instruments I know. I can hear a loose/flabby bass, a bloated midrange, a lack of treble extension. It’s similar to what people do every day when they tune their guitar or flute or clarinet. And I compare the gear in my home to what I own. It’s not perfect, but again it’s the best anyone can do I think.

Everything on the forum is opinion and based on individual experiences. You can say I’m arrogant. I can say you’d do better to not to get angry and recognize everyone’s right to post their thoughts and find a respectful way to disagree. I hope you can accept my response in the spirit in which it is offered, as a further explanation of how I characterize neutral. 

Acoustic Research ’sound’!

Any vintage: suppose seller says ’everything works! all new tubes!

My friend just bought a new to him Vintage Acoustic Research Tube Preamp, to replace his slightly older Acoustic Research Tube Preamp. He put new tubes in the existing unit, everything works, Acoustic Research ’sound’ right?

I went over, we did a few hours of comparative listening. The new to him unit was clearly superior, the existing unit’s sound much less focused, even wandered while listening to great Mono LPs, newer unit simply wonderful.

Some innards of the older unit ’work’, but not like they should, and if that was your first Acoustic Research listen, you would probably walk away, thinking Acoustic Research ’sound’ was not for you, and perhaps post negative comments here based on that single experience.

I do not believe in ’generalizations’.

btw, I ended up with so much more respect for his speakers after listening thru the newer Vintage AR preamp. What a difference.

I have nothing but good things about his AR Preamp/Amp combo's sound.

@soix 

"...everyone needs to define that inherently indefinable neutrality for themselves. I think this is a big part of the art — and wonderful, awful struggle— of ultimately putting together a great-sounding system." 

Great point.  The "struggle" part comes in when people chase some sort of holy grail of sound by constantly "upgrading" to equipment that others report to deliver "neutral" sound, when instead, they should simply trust their own ears and stick with the gear that sounds the most "natural" (i.e., good) to them.