Hi Gene,
What these ACD full bandwidth tests do is demonstrate whether the amp in question can do what the manufacturer says it can do, that's why I like them. I may be out of touch, but us little guys have no way of verifying what these manufacturers are saying their products can do. I like Reagan's old line, "Trust, but verify". If an amp is advertised at 80 watts by 5 channels, then it should be able to put out 80 watts x 5 channels to my way of thinking.
These amps may or may not be used with 4 ohm speaker systems, but Emotiva's speaker line is all 4 ohm. I don't know, however, if they recommend the UPA amps with their speaker lines.