Hi.
I'm trying to figure out impedance balancing in this Forsell summing bus.
http://84.255.203.119/SummingBuss2.pdf
I read about impedance balanced outputs, and it is said to be important that receiver stage (mix bus amp in this case) sees SAME impedances on hot and cold wires regarding to ground.
I cannot figure out why are, in Forsell-Sum-bus, resistors on cold lines 1k in size. Should't they be the same size as summing resistors? And if sum bus is connected directly to pan resistors (no post-pan opamp buffer), wouldn't that pan resistance count too, and even increase cold wire resistors? And how about pre-pan op-amp output impedance, would that count too?
How to determine proper size of these resistors? Are they usually calculated, or are they just set as 1k no matter imbalance?
thnx
gnd
I'm trying to figure out impedance balancing in this Forsell summing bus.
http://84.255.203.119/SummingBuss2.pdf
I read about impedance balanced outputs, and it is said to be important that receiver stage (mix bus amp in this case) sees SAME impedances on hot and cold wires regarding to ground.
I cannot figure out why are, in Forsell-Sum-bus, resistors on cold lines 1k in size. Should't they be the same size as summing resistors? And if sum bus is connected directly to pan resistors (no post-pan opamp buffer), wouldn't that pan resistance count too, and even increase cold wire resistors? And how about pre-pan op-amp output impedance, would that count too?
How to determine proper size of these resistors? Are they usually calculated, or are they just set as 1k no matter imbalance?
thnx
gnd