The ES-9 is a Eurorack 16-in/16-out USB audio interface, with DC-coupled inputs and outputs that can be used for both audio and CVs. With its balanced 1/4" main outputs & headphone socket, it's the perfect one-stop solution for integrating a modular synth and a laptop/tablet, either in the studio or when playing out at a gig.
The ES-9's 14 analogue inputs allow simultaneous tracking or mixing of a large number of sound sources in your modular, while the 8 DC-coupled outputs are perfect for controlling the modular with Silent Way, Max/MSP, Ableton's CV Tools, Bitwig Studio or similar, or for sending audio out to the modular for processing.
For even more outputs (up to 48 more), the ES-9 can be expanded with the ES-5*. It also has a pair of S/PDIF sockets for connecting other digital audio gear. The ES-9 also provides a pair of MIDI sockets (via a breakout).