Good preamp match for Bryston 4B ST


In process of upgrading. Currently have Bryston 4B ST, Dali Halicon 400 MkI speakers, and Rotel 1072 CD player. Listen to mainly acoustic music of all styles and prefer uncolored, if somewhat warm, musical sound with good imaging and soundstage. Already over budget a bit; would appreciate suggestions for a compatible preamp under $1K used.
Thanks in advance for any suggestions.
ricko
Thank you, Stevecham and Soix. OK, so here's my confession: I only recently acquired 4BST, and am not using it yet, but trying to get a good preamp match. The Dali 400's are a recent aquistion as well, so I'm still getting familiar with them. So far I think they are fantastic across the entire frequency range, but when listening to one recording, an older jazz recording from the 60's, the sax sounded a bit harsh and edgy. However that may well be his tone. As I've listened to other recordings, I get no harsness, but crystaline clarity in the highs (and rock solid, clean bass as well). I'm currently using a Rotel 1052 Receiver (100 wpc). Fine for what it is, but not a match for the Bryston and Dali's. My interest in a tube preamp was as a result of my ABing a Cary tube vs. a Cary SS pre at a showroom. The tube sounded more open, transparent, airy and fluid to me and I liked that. The dealer said, that's what you get with tubes somewhere in the chain. (Of course he was trying to sell me something.) Others (here) have suggested tubes, such as AR pres might be a good blend. Now, that said, although I have a good ear and know music, I am not savy elecronically, and when you guys start talking about matching output impedences, I get nervous. E.g., the AR LS16 has output of 600ohms balanced and 300 ohms SE. So would that match with the 4BST 20K and 50K? The Cary SLP 03 has output impedence of 500 on XLR and RCA's. (Would it work on the Bryston?) Moreover, most I can't find the output impedence listed for most preamps. Do I need to worry about this? Should I just play it safe and go with a Bryston, and put aside my tube dreams? Also do I need to put the Speaker impedence (4ohms) into this equation, or it that only and issue for Amp choice, vs. preamp, as I'd assumed. Help.
Thanks!
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Thank you Bob for your informative response. I was able to find a Bryston BP25 (without phono section, unfortunately), but I thought I should grab it as I assume there should be no problem matching it with the 4BST and using balanced interconnects. I'm still considering trying a tube pre, though, but I'm not sure (given the sparce information provided) which ones would mate well. Aljordan says the Audible Illusions worked well, but which ARC would work? Still would prefer a pre with a remote. Bob, why did you suggest the Benchmark?
Thanks
I had the 4BST mated to various tube preamps a while back but never cared for the sound. You may want to consider a Bryston preamp. I replaced it a Belles 150A and couldn't be happier, the Bryston was outclassed in every category except power output.
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