500 Series Dynamics: Many 500 Series compressors are based on classic models, which have been redesigned to fit the 500 Series format. You can choose from a number of types, ranging from opto to VCA to FET models. Some compressors include sidechain capability. Many feature VU metering, despite the compact size of the units. All the controls you’d expect are present on these compressors: threshold, attack, release, makeup gain, and ratio. Almost all models are mono, but when stereo needs come about, you can just link two units together. Many offer de-essing capability.