Thanks @Casanunda, I went looking and found @Jan’s explanation of it here:
TRS simply refers to the connector type. This becomes important information when connecting a microphone for instance, as with a TS input one needs to make sure the “cold” connection of the mics XLR goes to to the sleeve of the jack. Having TRS inputs makes the Dwarf compatible with XLR to TRS cables, and not just XLR to TS cables which are less common.
I take that to mean that the ring of the TRS input is shorted to the sleeve, i.e. grounded.
wouldn’t feeding a balanced signal while only having TS input lead to “no signal” getting in because you get the positive and negative signal on the same connection at the same time, cancelling each other out?
I don’t think so… with a TRS jack into a TS socket, the positive signal on T should pass through OK. The question is whether the socket’s S connects to the jack’s R or S. Whichever one it connects to is going to be grounded while the other would be floating. I’d expect to hear a signal in either case (although possibly with other issues like increased noise or ground hum?)
Which brings us neatly back to the use of the TRS socket with R grounded - it makes sure that nothing is left floating, whichever type of jack is used. Neat solution!
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