Terms

AAC:

A compressed audio format, designed to be the successor to MP3. It generally has better sound quality than an MP3 of the same size. AAC is Apple’s default file format for iTunes and the iPhone.

Active electronics:

An electric guitar or other instrument with active circuitry has an on-board preamp that boosts the signal. Active pickups generally offer wider dynamics and a fuller-range sound than passive pickups, but usually require an onboard battery to operate.