How to get balanced inputs working

Thanks, Dave. An inconsistency or reversal of pins 2 and 3 in the connections between the DAC and the preamp would only result in an inversion of absolute phase, though, which would at most have subtle sonic consequences on some recordings, and no consequences on many others. It would not cause the audio to be absent.

It is conceivable to me, though, that differences between the two preamps in how the grounding of pin 1 is handled could contribute to the (quoting from one of my earlier posts) "small differences in grounding conditions that may occur depending on which preamp is connected" that I speculated might "mean the difference between the DAC working and not working" when its input select switch is wrongly set to the XLR position.

That speculation is also, of course, a long shot, but regardless of what is going on it would seem clear that the switch on the DAC should not be set to select an input other than the one that is connected, whether it happens to work that way or not.

Best regards,
-- Al

Davehrab. Great shot , that was the final thing I checked , it's a German made for us market and it checks all out pins ok , great shot though dave that was my last kick at the cat thanks dave

The audio horizon dac 3 has an input selector that is used to select between either 1) RCA INPUT or 2) XLR INPUT. This selector does not have anything to do with the output selection.

From your above post, the dac is connected to the transport using a RCA connection; therefore, the dac's INPUT selector must be set to RCA for any signal to be outputted in either RCA or XLR output.

Do you get any sound when your dac is switched to RCA INPUT mode? It is not clear that you have tried this.

Lots of music when knob is set to RCA,

Pavpet, that is exactly how the audio horizon dac is designed to work. You do not have a problem.

If you change the transport to dac connection from RCA to XLR, you simply change the input selection to XLR.