Editing Ground loop (electricity) (section)

=== Isolation ===
Isolation is the quickest, quietest and most foolproof method of resolving hum problems. The signal is isolated by a small transformer, such that the source and destination equipment each retain their own protective ground connections, but there is no through connection from one to the other in the signal path. By transformer isolating all unbalanced connections, the unbalanced connections are converted to balanced connections. In analog applications such as audio, the physical limitations of the transformers cause some signal degradation, by limiting bandwidth and adding some distortion.