> If the 1176 is a line input device, why does it use a 15k:15k transformer? Wouldn't it be looking at a 600 load from just about any other line device?
OK, and say you had to feed a film-recorder, two tape recorders, a monitor amp for the control room, another monitor amp for the boss's office, and a tap for the press-box. If they are all 600 ohm input, the poor source is facing a 100 ohm load, and limps badly.
The customary standard for inputs is that they be 10K or 20K so that you can connect 10 or 20 of them across a 600 ohm output and cause no more than 0.5 or 1 dB loading loss. There are some exceptions: the Fairchild limiter is a solid 150/600 ohm input because it has a minimal audio path and can't spare the gain for a hi-Z input. But you normally prefer a hi-Z input(s) so you can bridge-on (or "wYe")any reasonable number of loads without affecting the audio level.
Yes, the transformer design is a little different if it sees a 15K source or a 600 ohm source. In fact I've seen "20K Bridging" trannies that internally had 10K of fixed resistor feeding a 10K winding. That way the low source impedance was buffered, but more importantly any crap or short on the bridging transformer output would reflect back as at-worst 10K resistive, not a low-low winding impedance.
