Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Good easy reference

Not too heavy on theory, but sufficient enough to get you started. Discusses different types of microphones, connectors, and their use in certain settings. This would be good reference for somebody starting up a garage band, or managing a small sound system in a school. It's a fast read, but doesn't skip over important details. Has good pictures to help explain certain concepts, a decent enough appendix with glossary and basic wiring diagrams.