Smalls sound is usually pretty poor for opening bands. When mixed well Smalls doesn't have bad sound by any means. Usually vocals are drowned out or mixed low.
The people that run the place are awful. I don't like supporting them. Luckily very few bands go there anymore.
Altar has consistently better sound. Their 21 and up section is better. The people who run it are good people.
There is a reason a lot of bands don't play Smalls anymore.