I have an AV receiver providing amplified outputs and preamp outputs.
The pre-amp outputs are in the form of (unbalanced) RCA jacks. My speakers are amplified and have a balanced input.
I was looking for an audio transformer to convert the unbalanced into balanced signal, but I read here that
If everything in your facility is unbalanced and the wires are fairly short, there's no point to using balancing adapters. But you can still reduce hum, if you're willing to do some soldering:
Use the same kind of two-conductor shielded cable as you'd use for balanced wiring.
Connect the "hot" conductor -- usually white -- to the center pin of the phono or phone plug at each end.
Connect the other conductor to the sleeve of each plug.
Now here's the trick" connect the cable's braided or foil shield to the sleeve at one end only.
Use shrink wrap or tape to make sure the shield doesn't touch anything at the other end.
Be consistent about which end of the shield gets connected... one way is to always connect the shield at your patchbay or mixer, and always leave the other disconnected.
Obviously this solution will result in a signal that is 6dB weaker than a real balanced one, but what are the implications concerning noise and hum immunity?
What is the length that should not be exceeded with this solution?