Mike and Simon, many thanks for these spot-on comments. I am especially impressed because while I don't understand 80% of your technical comments, the recommendations come through loud and clear :-)

As a related aside, the Eon One Compact has a built-in mixer for its four channels (two XLR/1/4" combo jacks, one 1/4" jack, and one 1/8" aux in jack). One of the XLR jacks has phantom power. It has basic analog controls on the body of the speaker, but the Bluetooth app offers impressive EQ/effects control over each individual channel, plus a master out EQ.

Unfortunately no USB input.