510 Chapter 17 C2 R6 C1 100 U 35 V NP R2 5532 56 R R1 22 K 3 C2 47 pF 47 pF In 10 K C1 100 U 35 V NP R2 Ground - + C1 100 U 35 V NP R2 5532 68 R R1 22 K CN1 Output Male XLR Ground R6 10 K R5 In 10 K - + Output Male XLR CN1 2 Ground R3 In 4K7 + - R5 4K7 5532 56 R R1 22 K 3 Output Male XLR CN1 + - 1 + - 1 2 C3 R4 R3 1K 100 pF 1K C2 100 U 35 V NP + - 1 R3 27 R R4 27 R R7 56 R R4 10 K - + R6 5532 68 R R5 22 K (a) (b) (c) Figure 17.3: (a) Inverting ground-canceling output; (b) non-inverting ground-canceling output; (c) a true balanced output. very low input impedance equal to the hot terminal output impedance so if it is used with a balanced input, then the line impedances will be balanced, and the combination will still work effectively. The 6 dB of attenuation in the R3-R4 divider is undone by the gain of two set by R5, R6. It is unfamiliar to most people to have the cold pin of an output socket as a low impedance input, and its very low input impedance minimises the problems caused by mis-wiring. Shorting it locally to ground merely converts the output to a standard unbalanced type. On the other hand, if the cold input is left unconnected then there will be 3 2