No one's harder on a sound man than another sound man. Need proof? Attend a rock show with an audio engineer -- who's not working the board. (Warning: I do this all the time and don't actually recommend it.) You'll swear you can see the off-duty engineer squinting his (or her) ears, dissecting the other engineer's every twist (or non-twist) of the knobs. What to the untrained ear sounds like a passably amplified song can torture someone who would have upped the high end or limited some subtle distortion.
Audio engineers -- and their ability to separate sound like so many threads of tone and buzz and hiss -- amaze me. But occasionally those magic ears fail, or the equipment does. And then, even those of us with less advanced holes in our heads for hearing can tell that something's wrong.
I didn't catch the 50 Cent concert at the Midland Theatre, but the next day, I noticed some negative Facebook chatter about how the venue "should do something about their sound or soundmen." A few days later, on Ms. Mermis' review of MGMT, commenter thePhantom* expressed with violent displeasure that "the Uptown's soundman should be shot on site."
That's some pretty harsh criticism -- maybe thePhantom* is secretly a soundman. But I don't really think so. If he were, he would know that the audio engineer who offended him was most likely not "the Uptown's soundman." Performers at the level of MGMT and 50 Cent will almost always travel with their own engineer. Even bands that only play small clubs will do the same as soon as they can afford it, which is why at the Riot Room or the Record Bar, you can often catch the house engineer taking a break when an out-of-town headliner goes on stage.
However, the sound of any show can also be a cooperative effort. Here's what Mike DuCharme, who works for AEG Live, says about the Midland Theatre:
We always have our house sound and light techs on hand and available at
every show, some of the touring acts carry their own sound tech / light tech and insist that they run their own front of house mix. Both 50 Cent and Talib Kweli were touring with sound engineers. When we can we prefer to use our own engineers because they really know the ins and outs of our system as well they are versed in running a digital board. Additionally 50 Cent was carrying additional subs and supplemented our in-house PA.