To clarify since there's been quite a bit of discussion on this topic, the ability to do phase/polarity reversal with out LDR preamps is ONLY available with our LDRxB model and then ONLY with special modifications including a special version of the firmware. Those with DIY balanced kits can also take advantage of this feature but again it requires modified input wiring and special firmware version. While I have never heard a change in sound due to polarity, I wouldn't mind readdressing the question. I am positive many people are noticing polarity as well as other aspects of sound that bypass my brain. I probably should simply be happy that the set polarity of my system works well for me, but if I do begin to notice polarity differences, it will give me another area to worry about, in true audiophile fashion. Is there a simple device I can insert in my system that will give me remote control of polarity? I am using a Tortuga non-balanced control which feeds 2 things -1. a DSpeaker controlled dual sub system and -2. a tube buffer feeding a 2 channel amp. I think with a little soldering I can come up with something but if a simple inexpensive small box solution exists I'd be interested.
For those who aren't steeped in this subject the essential purpose of phase reversal is to get the movement of your speaker cones to be in directional sync with how the music was recorded. The simplest example is a strike on bass drum with a mic in front of it. When the drummer steps on that pedal, the drum head's initial movement is outwards into the room towards the mic. Ideally, you want your speaker cones pushing outward (and not inwards) at that initial moment just like the drum head did.
Reversing polarity (phase) is relatively straightforward with balanced audio since you already have 2 parallel audio signals each 180 degrees out of phase with each other. By swapping these 2 signals you can reverse the phase to get the cone movement to align with the recording. There's no practical way to know which is right. If you have phase switching available, you can play with this and decide which way sounds best. It might be different for every track you play so it's not a one time thing.
With single ended audio there's no convenient way to achieve this. The only way I know of doing this is to convert the unbalanced signal into a balanced signal, reverse the phase connections, and then convert it back to unbalanced. I would argue that nothing good will come of doing that unless an extremely high quality signal converter is used.
There's one additional way to achieve phase reversal but it's clumsy and not particularly satisfying. Just swap the +/- leads of your speaker cable either at the amp or at the speakers. Not practical to do this back and forth in real-time as you listen to music.
Best,
Morten
