The wiki has been upgraded to MediaWiki 1.43. The wiki's theme is still being adapted to work with the new version, and may appear broken for the time being. --RanAS
Echo Mixer
From SnesLab
The Echo Mixer combines all the voices which have echo enabled on them (via EON), as well as the Echo Feedback, when the Echo Buffer write enable flag (bit 5 of FLG) is set.