Balanced/unbalanced

Still trying to get my head around most optimal approach for interfacing with balanced and unbalanced equipment.

To make things even more unclear, things can get more complex if equipment have floating signal ground. Meaning that chassis ground and signal ground is not connected. My understanding is that these should always be connected, but as I have seen professional equipment where this is not the case, I guess there is a explanation and reason for doing it this way also.

Terms pseudo balanced and impedance balanced are sometimes used as synonym. Impedance balancing is a method where cold signal doesn’t contain any audio. Instead it is usually pulled to ground through identical passive network than hot signal. Most cases a single resistor. This allows cold line to float and up pick up interference similarly as hot line. Which can then be cancelled out at the receiving end.

In many sources pseudo balanced is used to describe a cable that has balanced connector on the other end while other end having an unbalanced connector. But the cable has been wired such that there isn’t anything balanced in it really.

What I will need to test at some point, is to make a custom unbalanced to balanced cable, where impedance matching is made inside the cable connector. Which is in many cases a single resistor. You will need to know the circuit of the hot output which you can either simply check from schematic or device itself. Or you can measure it. Doing matching inside the cable would then allow you to keep the original device as it is while still be able to enjoy benefits of impedance matched connection.

Here is list of sources I found helpful in figuring out how to wire an optimal cable for whatever devices you want to hook together:

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