Hrad is an expander for Praga four–channel stereo mixer that adds new functionality and enhancements. Hrad features a master section with stereo volume control over the overall mix with five-bar LED stereo level indicator, a stereo sum output that is switchable between eurorack and line level, a headphone output with volume control that is independent of the main attenuator, a special cue input that can be auditioned with and without the mix, four control inputs for automated muting/unmuting of individual channels, four inputs for voltage control over the aux send levels, four insert points in the aux sends, and two stereo attenuators for Praga’s two AUX return pairs. For detailed description, please refer to the manual.