I tried an Ei today in the phase inverted of my CCV. I found one that had really high TC and MU. I took out the 6N4j. I noticed immediately that the amp was quite a bit tighter and had a bit more gain. The Ei was rated higher than the 6N4J, so that was expected. Full chords had a pleasant grind to them and we’re very full... but what was interesting was that single notes were clear and focused sounding. Two note chords had that same clarity which I really prefer. For now, I keeping the Ei in the phase inverter.