The simplest way to test a bulb is to try it out in a fixture that you know is working properly. If the bulb works, it's the other fixture that has the problem. If you don't have another fixture for this simple test, you can test the bulb for continuity with a multimeter or cont...
the filament is electrified and provides high resistance to the current, which causes the filament to glow inside a confined glass globe. This creates light, but also a lot of heat. With fluorescents, the electrical current is directed through a sort-of transformer called aballast, then...
You might try to use a multimeter to see if either of the brown wires is common to either of the red or black power supply terminals. This might give you a shared ground with the other amp. Otherwise I think you can put capacitors in series with the output wires to block any ...