A port without a matrix sent source channel n to destination channel n, so a
mono voice reached only the left channel of a stereo mix. The PS4 firmware
11.00 libSceNgs2.sprx mixes such ports, and ports whose matrix levels were
never set, through a fixed channel map instead: mono reaches both stereo
channels at -3 dB and the centre of 5.1 and 7.1, stereo folds to mono at
-3 dB per side, and wider sources fold down with 0.5 and -3 dB gains. The map
was measured for every source width into 1, 2, 6 and 8 channels.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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