I have the development LDRxB-v2 with Morten's implementation of the absolute polarity/phase reversal option. I can tell you that sonically, the addition of that option introduces absolutely no sonic degradation. I've owned or auditioned various components that offer the feature, but with mixed success. The best implementations have exactly the same signal path with the inverted as with the non-inverted setting.
Successful implementations include DACs where the normal/inverted setting for a DAC is implemented in software. So the alternate settings have the same signal path. I've heard preamps with the feature, but the implementation is usually via a switch and sometimes even with one of the alternate settings going through additional wiring, even through an additional stage. My experience has been that the simpler path always sounds better, but not because it is the correct phase/polarity setting, but because there are fewer components in that path than the alternate path. To me, it's also mandatory that the selection between the two settings needs to be able to be performed from a remote at the listening position. Having to walk over to the DAC and switching the setting and then returning to the listening position to evaluate the difference gets old... really fast.
Also, if you rely on using a DAC with the feature you may be all set, but if you use a turntable or another source that doesn't go through the DAC, you're out of luck.
Morten has managed to add this feature without increasing the complexity of the signal path and without having to introduce the dreaded switches that the LDRxB (and the other Tortuga controllers) have completely eliminated. It works with any type of input whether it is a DAC, turntable, or tape. Quite a nifty piece of engineering.
Currently in my LDRxB, the normal/reversed setting is indicated by a single pixel at the lower right corner of the right channel level display. The only problem I have is that my listening position is about 18 feet from the Tortuga and it is almost impossible to see if the pixel is off (normal) or on (reversed). It isn't all that big of a deal since I'm not obsessive enough to go through my recordings and identify the correct settings for each. Besides if you're listening to a streaming source, a movie on TV, etc., then you have to choose the correct setting on the fly. Easy enough to do since the change between the alternate settings is easy to hear and is consistent across recordings (the difference that is, not the phase/polarity setting). This post is getting long enough already, so I'll save the description of the differences for a follow up.
As Morten indicated, the only lingering issue, at least for me, is to determine if there is a way to more obviously indicate whether the Tortuga is set for normal or reversed without mangling the simple elegance of the Tortuga display. We've had several discussions (thanks Morten for your patience), which always seem to come down to a neat way to indicate the difference versus the complexity to program it into the system. Whatever becomes the final implementation, I suggest keeping that single pixel normal/reversed indicator in addition to any other indicator since some of the display options would allow the user to define a display option opposite from another user (e.g dimming a bit the left or right LED brightness level).
Again, thanks Morten for a sonically flawless implementation of this feature.
Best,
Robert