My mistake, I thought this is what you were after. This is a cut and paste from the ML site
Comprehensive Inputs and Outputs with Simultaneous-Connection Option
Grotto i provides a direct, unfiltered LFE input for connection to surround preamp/processors and receivers with built-in subwoofer crossovers as well as line- and speaker-level stereo inputs that connect to its internal crossover. The LFE and stereo inputs can be connected simultaneously with separate level and crossover settings for each, enabling precise optimization for home-theater and stereo music playback in the same system. For those who desire a multiple subwoofer setup, line-level outputs include a mono jack that carries the sum of all inputs. Further, stereo outputs pass a signal from the stereo inputs either directly or through switch-selectable high-pass filters.