M mdram Golden Member Jul 5, 2018 #26 Jan 2, 2014 1,445 10 106 Jul 5, 2018 #26 FeuerFrei said: How does that work? Is there a special 3-channel encoding format? Or does the receiver matrix the right / left channels to create a center channel? Click to expand... sorry, been away. the avr maps those other channels to a speaker that is there a decent avr does wonders most broadcasts are 5.1, some are in stereo.