The Handbook of the XDA -1 output specifications are confusing: Nominal Output Voltage: 1V RMS • Peak Output Voltage: > 12VRMS (balanced) Firstly what is nominal : I understand this to be a sine output whose peak is the maximum possible ie fully coded to 0xFFFF. This is however in conflict with a peak output voltage of 12 VRMS balanced as usually the balanced output is double the unbalanced output.
Why I'm being so pedantic is that I have a Krell power amp ( only 26 db Gain ) and this needs a minimum of 2.5 V rms unbalanced to drive it fully. Furthur you will need at least another 6 db of headroom for those CD/DVD that are recorded just below maximum possible levels
I have been caught out with two previous preamps with confusing specs ( Parasound and Yamaha ) so I don't want to be caught out again
You should be fine with the XDA-1 driving that Krell since it is designed to act as a pre-amp as well. If I remember correctly, the output voltage on the RCA out can hit around 7V. I have used one to drive amps directly through a passive and it has worked just fine.
Speakers: Monitor Audio RS8's, RSLCR, RSFX
Subs: Dual Epik Empires
Powered by: Dual XPA-5's & XMC-1
TV: Samsung 52" A750
Sources: Pio Elite BDP-05fd, Toshiba HD-A30, DirecTV HD, HTPC
Extras: Music Hall 25.2 DAC, JoLida JD9, Panamax 5100 (x2), Roku