The most common listing of 90 degrees out of phase corresponds to Haeco's own recommended setting of the +3 dB build up, whereas no build-up would require a 120 degree offset. This setting was most commonly used because of its robustness against polarity reversal of audio interconnects down the chain, which can affect the resulting audio when downmixed to mono. Information that is not common to both channels is entirely unaffected as there is no offset phase wave to cancel with.