Recommendations please for good, affordable pre-amp for system?

@jond , if you scroll down, you'll see the details below the top stuff. 

I like the thought, expressed here I earlier think, that buying the preamp is as hard as the speakers. Surprisingly to me, although budget is not unlimited, I find myself a little bit expecting a process of buy-play-try. I anticipate, as long as I keep to auction and used, I can try, and recycle, and not get hurt too badly. Although surely the best is to find a local dealer who can demo this element is best, I think that's going to be hard in my area.

I expect to receive amp and pre within a few days. I'm looking forward to plugging this in and beginning this new life of audio!

A used Quad 99 is pretty decent and has useful tone controls for helping Internet radio out a bit ☺

I'm a huge fan of the AMC CVT1030 tube preamp which can be a bargain on the used market. They usually need a bit of work but are very satisfying. I know these units inside out if you ever get one and need advice. 

There are lots of opinions and there are some people who hear more things than others and people who prefer some sound personalities to others.  No one here is going to be able to tell you which preamp work best with your amp, speakers, sources, etc. without guessing or without putting their personal tastes into your system.

You have some expensive, demanding speakers.  You got a well-respected amp.  If you bought a $300-500 Bryston preamp, you might love it, you might not.  But just because someone tells you that tubes add warmth doesn't mean that warmth is necessarily a good thing or that tubes are better.  My Aikido preamp is not a high-end tube preamp, but it does add a certain sound personality.  I went back and forth between it and the Pass endlessly before settling on the Pass.  I may go back to the tube pre one day, but for now, I'm perfectly happy with a simple, easy-to-use solid state setup.

Based on how you've been in this thread, I suspect you are at the beginning of months or years of buying, trying, selling, trading, building. 

Look in an Andire  Diffet 2 preamp. Used within your low budget but vary neutral with abilities you need. Not well known but built in USA and good owner. I owned one and their Forte power amp. It was a good combination, but ultimately upgraded the amp twice before I needed a better preamp.

I’d recommend a TVC passive as it’s going to avoid most of the issues with impedance matching, will give you a very very low noise floor (prob most important quality for a preamp) and unlike other passives, they are still revealing at low volume levels (if you’re in an apartment, for ex). It also won’t need a socket.. no power cord). $500 preamps w/ AC power supplies are usually nasty sounding devices. Back to TVC, at around your price range.. the only ones you might want to consider are the Mingda TVC passives available on eBay. For the higher end I’d recommend a used Stereoknight or the newer similar version made by Audio Music (the RS).. it’s fully balanced. but for $350-$700, Mingda makes both a single-ended version and a balanced (XLR) version with two volume controls. You may not find it on eBay.. but just message them there. Fyi, these are simple devices.. so integration with home theatre will still require an additional ht processor device with ’pass through’ if you’d like to use multiple inputs/sources, but in general TVC’s will give you your best bang for buck. Another option is to pick up a used Rogue Metis for under $700 (stick with stock replacement tubes from Rogue). If you need it, the Rogue with thicken your musical stew in a good way. For transparency, a TVC will give you the cheapest most non-degrading volume control possible for the least $.