This is a spin-off subject from the "Women belong..." thread.
What I found to be most interesting is that the same sorts of issues that pertain to audiation at the parish level were quite evident in the Epiphany Masses. The female lector Mr. Culbreath mentioned elsewhere was possessed of a beautiful, silvery lyric soprano voice. She also seemed to "use" the microphone at the ambo. However, neither of those realities enabled me to understand a single phrase of the Epistle. I was seated in the middle of the church. To be fair, there were also some occasions where male proclaimers did not elocute their sung readings with audible clarity. And there was one celebrant who suffered from a lack of projection and pronunciation. Even Dr. Schaefer, generally very precise, seemed disposed to draw the listener's attention by very mannered (and beautiful) and modestly voiced Gospel renderings.
On the other hand, we were privileged to hear three celebrants who clearly understood the acoustic and ambient demands of the Epiphany space, and without benefit of amplification, provided amazingly clear and beautiful orations on repeated occasions, from various locations in the sanctuary, and even in the ballroom locales.
Microphones and PA systems should be, basically, irrelevant to the solo singer.
The physical demands upon cantors and psalmists cannot be underestimated. But the mental preparation and sensual awareness must be factored in prior to their taking of the ambo. It seems to me that anyone preparing to sing a solo section of an Ordinary movement would apply the same vocal principles to the canting of the lessons.