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TL Audio. We have several of their PA-1 and PA-2 mic preamps and they are great. Two channels, valve circiutry, very quiet very clean, and supurb sound. We bought all of them used for between $350-500 each. For about double that we bought the dual valve mic preamp/compressor. Same preamp with a full function tube compressor.(The latter usable as an insert on it's own also.)
They both blow doors on ANYTHING in that price range.
I'm actually thinking about selling one of the PA-1 preamps, as I loved them so much I really bought too many. If you're interested e-mail. Check our website for recordings done with these mic pre's.
Good Luck