Up for sale is the Tascam Celesonic US-20x20 audio interface/digital mixer/8 channel high definition Ultra-HDDA microphone preamp in excelent condition. All 3 functions are separate and switchable. The 20 channel digital mixer includes eq and compression on each channel and has 4 auxiliary sends and built in high quality reverb return section. (See image) . All 8 microphone preamp channels include Tascam's Ultra-HDDA high definition circuitry with top of the line converters. The unit supports super fast USB 3 connectivity to your PC or Mac. There are too many options to list here. If you have any questions send me a message and thanks for looking.