The G68 variable analog outs range from 0 to 3.5 VRMS. Your amplifier should reach full rated output at 3.17 VRMS. That said, it should have no problems driving your amplifier and speakers to adequate levels. On the G68 I find that my normal listening level is around 65 so most people will run in the upper end of that scale. I haven't gone digging to find the specs on a analog output card for an 861 but I am quite sure they are very similar to the G68 so changing from one unit to the other would not likely give you any more gain unless there is something wrong with the cables connecting the equipment or the G68 analog out. It would be worthwhile to check the cable impedance to ensure that the value is not too high.

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