Here's a review I just posted to Google for the Echo, Los Angeles, CA, titled "The acoustics ruined my chance to see a band I love (2 stars out of 5)"
Right now, sitting at my desk with my decent computer speakers, I'm listening to the debut album from Cymbals Eat Guitars with an empty feeling at the incredible experience of which I was robbed. My wife and I went to the Echo last night to see Cymbals Eat Guitars and were sorely disappointed with the sound. The system was simply way too loud for the room (like, conservatively, 12+ dB, often exceeding the pain threshold in something like a 4000 sq. foot space with nowhere to run) and the bass was boosted so far that everything above it was masked, which precluded earplugs from being a viable option. It was so bad it could have been a joke, albeit a terrible ear damaging joke.
I give the place two stars instead of one to entertain the possibility that just maybe these weren't the regular sound guys and it's not always like this. It's a real shame. Everything else about the place is good: the size and decor are cozy, the bar was generously stocked (though we didn't drink last night), the crowd was cool except for the usual couple of outliers, and the bands that come through are really great.
Fix the sound!! I'd consider reporting these guys to OSHA with purely artistic motivations.