Look up and call http://www.theaudiosolutions.com/ (317)255-4434 and ask Graham. He sells both B&W and Mac.
2 responses Add your response
If you don't push your amp near its limits, going with the any setting should be fine. Setting the amp for lower impedance usually can't hurt anyting except distortion levels. If you work the amp/speakers hard, then the speakers will be pushing lower impedances and may sound better set at 2 or 4 ohms. Just make sure that the amp is OFF before changing your settings.