erik_squires
Once a phono cartridge is connected to an unbalanced input, the cartridge is no longer "balanced and isolated."
If the phono cartridge - which as you note in inherently balanced - is connected to a truly balanced phono input, there should be no ground loop or hum problem. If there is, it suggests an issue with the cartridge itself or the pickup arm wiring that results in unbalancing the phono circuit.
So, my statement was "Balanced and isolated"The phono cartridge is only "balanced and isolated" if it's fed into a balanced phono preamp. But very few phono preamps are balanced. (Of those that are, not all meet the AES balanced spec, an issue Ralph frequently points out here.)
Where is the ground contact happening at the cartridge side?
Once a phono cartridge is connected to an unbalanced input, the cartridge is no longer "balanced and isolated."
If the phono cartridge - which as you note in inherently balanced - is connected to a truly balanced phono input, there should be no ground loop or hum problem. If there is, it suggests an issue with the cartridge itself or the pickup arm wiring that results in unbalancing the phono circuit.