550 Chapter 19 1K +3.5 dB Level trim -6 dB 110 R +2.2 dBu 1.0 V 220 R CN2 Male XLR HF out + 3 180 R Impedance balance resistor 1 - 330 R +3.5 dB Level trim -6 dB 110 R +2.2 dBu 1.0 V 220 R 2 CN3 Male XLR MID out + 360R +2.2 dBu 1.0 V 2 CN4 Male XLR LF out + 1 - 3 Impedance balance resistor 1 - 3 Impedance balance resistor 2 150 R 180 R 120 R Figure 19.6: Reconfiguring the output networks for impedance-balanced operation with power amplifiers fitted with balanced inputs. impedance driving the hot (+) output pin. This improves the balance of the interconnection, as fully described in Chapter 16. In our circumstances here the output impedance of the level-trim network varies as the wiper of the preset is moved from one end of its travel to the other, and so the impedance from the cold pin to ground is inevitably a compromise.