This is the original Presonus Digimax 8-channel mic preamp with the separate power supply. It is HEAVY! These things sound great. It can be used as a stand-alone 8-channel mic preamp with direct line output for each channel (no computer required at all), or an 8-channel mic preamp/converter with ADAT lightpipe output (to add 8-channels to an existing DAW). It also has an 8-channel AES/EBU digital output on a a multipin connector. Most of us used these to add 8-channels to our existing DAW with the ADAT output—-it will use the clock from the existing host converter. Each channel also has a limiter with an adjustable threshold. This one was removed from a working environment and sounds great.