The OC8E 8-Channel Optical Compressor from SM Pro Audio features eight independent channels of optical compression and is designed to be used for inserts on multi-track recording and mixing projects. Each channel has its own attack, release, compress, and output level encoders. Its eight independent analog VU meters display the channel's output level. The tri-state LED indicators glow green to indicate when the channel is active, yellow/orange to indicate mild compression, and red to indicate heavy compression. The OC8E has a Class-A transformerless signal path and a 100-volt to 200-volt internal power supply. It features a metal housing and is rack-mountable, requiring 2 rack-units.