How does the inductive spike route through mains and effect this kind of system?
How does the inductive spike route and effect the transducer or its coax line? Would that happen as a conductive or radiate way? How does the conductive way routes all the way to the transducer system?


It's a pulse of HF with a wide spectrum, so it will be a mess.

It begins as differential-mode across the switch.

Consider the electrical path from the arcing switch to the "receiving" device: this isn't exactly shielded controlled impedance coax cable. Let's say it runs in differential mode along wires inside conduits.

Every time one of the wires gets close to something conductive (wall studs, your fridge, anything) then the coupling between both wires and said conductive object will be different, thus some differential to common mode conversion will occur.

By the time it reaches your device, some of it will be common mode.

Now it reaches the transformer: let's say it's an EI core, in that case one "side" of the primary will be a lot closer to the core than the other side. At this point, via capacitive coupling, more differential to common mode conversion will occur.

It it's a toroid, then the boards and other stuff inside the enclosure will have more coupling towards certain parts of the primary coil than others, so same effect.

Now say you have a CD player connected to an amp... both have different transformers wired in different ways, so the differential to common mode conversion will create different levels of common mode noise for both. This creates a common mode current across the unbalanced connections, and a loud crack is heard in the speakers every time the fridge turns off.

Fix is either at the source (add a capacitor to prevent arcing) or at the receiving end (add IEC mains filter, or plug everything in a filtered outlet).