Congratulations!
You need an XLR cable which essentially flips the HOT/COLD. Pins 2/3 are “backwards” on the H3000.
route H3000 pin 2 (- PHASE) COLD >> to pin 3 (- PHASE) COLD on the other rack gear.
route H3000 pin 3 (+ PHASE) HOT >> to pin 2 (+ PHASE) HOT on the other rack gear.
pin 1 remains signal ground.
Most rack equipment I/O pin 2 as HOT(+), so when you output or input into other gear with a regular cable, it will FLIP the phase.
If you want to unbalance the H3000 input (1/4″ TS jack), connect XLR pins 1,2 (COLD/GND) to 1/4″ ground (sleeve), pin 3 (HOT) to tip.
If you want to unbalance the H3000 output (1/4″ TS jack), connect XLR pin 1 to ground, pin 3 (HOT) to tip, and leave pin 2 (COLD) unconnected. Pin 2 is left unconnected because the NEC5532 output driver (opamp) produces less harmonic distortion with its cold (-) pin open (not shorted to ground).
Hope this helps.
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