RME AO4S-AIO overview The AO4S-192 from RME is an analog expansion board that adds 4 professional quality analog outputs to the company's HDSPe AIO PCIe card. Level adjustment, balanced circuit design, 118dBA signal to noise ratio, and the highest level of PC-noise suppression guarantee perfect sound quality. The converters offer the same performance as the on-board stereo analog I/O of the HDSPe AIO - up to 192 kHz resolution, balanced connection, and the choice of 3 different reference levels, selected in the settings dialog. The expansion board can be used with the HDSPe AIO and the HDSP 9632 to provide a maximum of 6 channels of audio output when combined with the 2 channels of I/O available on the main board. However, no more than one AO4S-192 AIO can be connected to each card, although a combination of an input and output card is possible. Analog output expansion card for the HDSPe AIO and the HDSP 9632, adding an additional 4 outputs to the system Servo balanced outputs on 1/4" TRS connectors Choice of 3 different reference levels Up to 24-bit/192kHz resolution Can be combined with similar input expansion board