phase control on BAT VK pre amps

The following CD has a test that will enable you to tell if you can actually hear the Wood Effect. It also contains test for proper sound stage(left and right imaging), the LEDR test, etc: (http://www.amazon.com/Chesky-Records-Sampler-Audiophile-Compact/dp/B000003GF3) Notes on the Wood Effect here: (http://mariobon.com/Glossario/Fase_Assoluta.pdf) LEDR info here: (http://www.stereophile.com/features/772/)

The Chesky disc has two demos, in which phase is reversed. The first with one trumpet(actually two tracks, one reversed). The next with a full jazz band, which they reverse the phase on, without telling you at what point. My son and I both noted the exact moment of reversal, different days, no prior discussion. I own a number of recording(CDs and vinyls) that I have marked for reverse phase playback. As Ralph mentioned; there are many more in which no differences will be noticed.

"Keep in mind that the Chesky CD is made for demos. Most likely, they selected tracks that emphasize whatever quality they want you to hear." GEE, Ya think? Chesky recorded those tracks, and reversed the phase, to demonstrate the Wood Effect, and enable one to see if they can discern it. That WAS the point!

Same reason I have some vinyls marked as to optimum tone arm height/VTA: I only have to reverse the phase of a recording once, to determine whether it's worth reversing or not. I may not remember the best phase, if I don't play that recording again, for 6 months, a year....

Mr L: Both my CDP(a BAT) & phono stage have phase switches.
You are correct; in that if one has no other means,
reversing the leads to one's speakers would be the option.
BTW: When that LED is lit; it means your phase is inverted.
Obviously; Misters Bednarski and Khomenko(et al) regard phase
accuracy as something to be addressed. They DO seem to know
something about music reproduction!