Applying effects to a track is not simply a matter of flicking a switch. Each effect has parameters that need to be adjusted. GarageBand takes some of the guesswork out of choosing effects settings by providing presets for most effects. The presets for each effect appear in a pop-up menu to the right of the effect's listing in the Track Info window. Next to each effect's presets menu is an Edit button, which opens the settings window for that effect so you can customize the effect. You can save your customized settings as a preset, and it will appear on the preset menu. Some of the simpler effects (gate and compressor, for example) are adjusted with a slider. Effects controlled with a slider do not use presets.