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


Hi All, 

I'm configuring my first system, and have so far acquired the speakers (Thiel 3.6) and amp (Bryston 4B SST). I believe I need a preamp to complete this (and I believe only a preamp, right?). And I'm hoping you can give me some leads, information, and recommendations.  It's a 2-channel setup, and while it would be nice to add some HT capability in the future, I'm seeking as pure a sound as possible.

Some things I've looked at are Theta Casablanca, Bryston 0.5B, and perhaps for future upgrades, model Rotel RSP-1582 and Marantz AVR8802 -- although I'm concerned that those latter two, while brining nice features, will work to molest the signal.

Prime listening will be CD, with some lossless Network-attached storage, and Airplay with Tidal or otherwise Internet radio.

Thanks for your recommendations!
donzi
There is a Parasound P-3 Pre for sale here on AG. Asking price is $450. Might be one you could use until you upgrade and sell without much loss.
Thanks all, for all your thoughtful and detailed comments. It's incredibly helpful, and I've started a new bookmark folder just for these suggestions. A world of information here! Thanks a ton!
A used Placette Remote volume control would offer the highest performance possible in a passive in this price range. The Bryston has 1.3v input sensistivity setting which would help overcome any passive limitations. The use of a passive also depends on your sources. If the source has enough oomph the Placette will give incredible dynamic and bass performance along without blurring the sound with an additional gain stage (engineering seems to fall down in the area of passives, but oomph might be voltage output and lower output impedance). If your sources have oomph, I'd put a Placette on the used shopping list and check it out. This model only has one input and one output, but other flavors of Placette are possible that add features including balanced connection.
I use I used a McCormack MAP1 that has 2 sets of 6 in/6 out and 3 stereo sets of inputs. Totally passive and very clean for the price. I used a Bryston 9 bst and a powered sub with very good results. Obviously I had to settle for 5.1 sound on movies. The 2 channel was better than any pre/pro I had, and I tried a few. My source was an Oppo which did all of the prrocessing and I used the better stereo outs on the Oppo directly in to one of the stereo inputs on the McCormack. 5.1 SACD sounded good too. They come up on Agon rarely, but are pretty reasonably priced, around $700.