Balanced Tube Preamp Recommendations for $2000

Are you looking for a fully differentially balanced preamp - from input to output?  Many tube preamps (including the Backert) with balanced outputs are either a hybrid design or use transformers, so they are not truly differential.  Maybe you could reconsider this criteria unless you think it is somehow mission critical due to grounding issues or long cables runs for example.  It opens the door up to many more possibilities, especially within your budget.

It will be tough to find a true differential balanced tube preamp for $2,000 used. 

The Calypso’s balanced output impedance (measured by Stereophile to be 112 ohms at 1 kHz and above but a very high 3900 ohms at 20 Hz) is marginal at best with respect to the balanced input impedance of the XA30.5 (spec’d at 30K and measured as 29K by Stereophile).

The LS17SE as well as most other ARC line stages don’t provide a lot of margin either, having a recommended **minimum** load impedance of 20K. And it isn’t clear if that recommendation applies to its balanced outputs or its unbalanced outputs or both.

Finally, I agree with some of the others that you are unlikely to find a high quality fully balanced preamp meeting your various requirements for $2K used. And a preamp in that price range providing balanced outputs while having an unbalanced internal signal path might sound better if you were to use its unbalanced outputs and drive the amp single-ended. Note, though, that Stereophile measured the unbalanced input impedance of the XA30.5 as being 20K, so if you were to do that you would want the preamp to have an unbalanced output impedance of no more than about 2K at all frequencies.

Good luck. Regards,
-- Al

So you could use one of the schiit Freya's inputs as a home theater bypass. Just set the amp to passive mode and turn the volume all the way up - that's what I do with my passive preamp. Just make sure to turn the volume down before switching inputs and changing source material!