Sony HT-DDW970 Operating Instructions Manual page 26

M Playback channel indicators: The letters
(L, C, R, etc.) indicate the channels being
played back. The boxes around the letters vary
to show how the receiver downmixes the
source sound.
L (Front Left), R (Front Right), C (Center
(monaural)), SL (Surround Left), SR
(Surround Right), S (Surround (monaural or
the surround components obtained by Pro
Logic processing)), SB (Surround Back (the
surround back components obtained by 6.1
channel decoding))
Example:
Recording format (Front /Surround): 3/2
Sound Field: A.F.D. AUTO
L C R
SL SR
GB
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