I have no relevant experience but I would point out that the input impedance of the Soulution 511 is an extremely low 2K (balanced only). That would make it unsuitable for use with the majority of tube-based preamps, and with some solid state preamps as well. That is not an issue with the Luxman.
I would note, though, that the Luxman’s balanced inputs have XLR pin 3 "hot" (i.e., non-inverted relative to the polarity of the signal on the red output terminal) and XLR pin 2 "cold" (i.e., inverted relative to the polarity of the signal on the red output terminal), that being the opposite of what is usual for USA-made equipment. So to maintain absolute polarity the + and - connections to the speakers would have to be interchanged at one end, assuming no other polarity inversions are present in the signal path. And doing that **might** be a problem if the speakers incorporate powered woofers, or are otherwise powered, as in that situation the signals on the amp’s + outputs **might** be connected to ground by the speakers, either directly or through some low impedance. (In that situation an alternative approach to achieving correct overall polarity would be to use a pair of XLR cables between the preamp and power amp which have the connections to pins 2 and 3 interchanged at one end).
In any event, depending on the preamp that is used the low input impedance of the Soulution is likely to be a far more serious concern than the Luxman’s polarity reversal.
Good luck. Regards,
-- Al
