Having a basic understanding of the anatomy of your guitar amplifier will go a long way towards getting the most out of your system. While designs vary and there are a lot of model-specific features available, all guitar amplifiers have the same basic components, with additional optional components adding features to the more complex models.
When it comes to live amplification for guitar and bass players, there is a critical balance between the sound requirements for the audience and the stage volume needed by the artist to comfortably perform. While the same is true of any musician, it presents a particular challenge for guitar and bass since the amplifiers are designed to color the sound of the instrument, and many vintage designs don’t sound their best at lower volumes. The refrigerator sized bass stacks and hundred watt non-master volume amps of the past are examples of amps with too much power to use effectively in any but the highest volume situations.
Have you ever been frustrated because you worked very hard to get a certain sound perfectly dialed in, but then something changed and it seemed like you were playing through a different amplifier? Maybe you took your cool new amp to a show and it didn’t sound the same live as it did in rehearsal, or perhaps you sound-checked for a gig but when the show started your channel levels seemed out of balance? It can even happen in the middle of your set for no apparent reason (and you’re 20 feet from your amplifier)!