Neil: Audio manufacturers claim as much as 15 dB improvement. What if you need 40 dB? The REAL problem is Pin-1 related. If you are not up on the Pin-1 issue, log on to www.aes.org and order the 6/95 issue of the AES Journal. Article title is "Shields & Grounds". Pin-1 problems and how to identify them is extensively explained. There are literally hundreds of references.

Joel: So if Pin-1 of all my equipment is connected to the chassis and not the zero volts of power supply, am I basically immune to noisy grounds?

Neil: You should be, and can verify this by using the methods outlined in the AES paper.

Nicole Like: So, you're saying we don't need to do anything to protect our equipment from magnetic fields other than apply a SurgeX and forget it?

Neil: Magnetic fields from computer monitors can couple into other equipment. This is a magnetic issue. SurgeX prevents power line disturbances from getting into equipment via the power line.

Bill Grant: In an emergency situation, are transformers a good way to fix the Pin-1 problem?

Neil: Yes, because they can be wired to provide galvanic isolation. Simply lifting cable shields at the receive end (balanced circuits only) will effectively mitigate a Pin-1 problem for that circuit.

Nicole Like: Essentially, though, it sounds like if you have SurgeX protection, there's nothing else to worry about in regard to any type of electrical interference.

Neil: As far as power line noise, yes. But magnetic fields produced by nearby equipment can induce noise. Wall-warts are a particular problem. Moving them physically away from equipment is a way to deal with that problem.

Joel: Would I get any performance degradation if I use an input transformer in a device’s output, and vice versa, due to their different constructions?

Neil: Yes. But this is a question that should be directed to Bill Whitlock at Jensen Transformers.

Bill Grant: About inductive surges on signal lines, is conduit a good method of prevention here?

Neil: It won't hurt. But if it’s a magnetic coupling issue, what does the job is the twisting of the signal pair. Shielding will keep out E-field energy, while twisting keeps out H-field energy.