Using the balanced output of my RME ADI-2 DAC, set at +13 dBu (so actually +19 dBu at the XLR output) into the XLRs on the Phonitor X, driving my HD650 from the balanced output, I have a perfectly usable range of volume output up to 12 o’clock on the volume dial.
That’s a significantly higher level of output than you’ll get from a Gungnir MB via it’s balanced outputs.
But, again, that’s with the “X” … I’ve not tried it with the “e”. While I assume they have essentially the same amplifier topology and fundamental implementation I’ve not tested that personally (nor am I likely to).
It does … and personally I wouldn’t buy a Gungnir MB (or DS, for that matter) if I wasn’t going to use its balanced outputs (or at least in the very near future). Yes, it’ll still sound better single-ended than a Bifrost MB. but not enough, for me, to warrant double the price.