I wonder what kind sound not-impacting methods exist to connect and disconnect signal from moving coil cartridges.  If we are talking about the switching the .1mV signal and monitor the results within a fairly high capacity playback then it become quite difficult to find a transparent switch.  In my past I have tried all imaginable switches: mechanical, some sealed relays and some crazy super expensive mercury switches. None of them were transparent enough. Some sources suggest that the gold relays in inert gas environment might be preferred way to go when the voltage is low…Perhaps to drive the relay’s coils by DC batteries….

Does anyone have any success story how to switch the ultra low voltage (.1mV-.5mV)?

Thanks,
Romy The Cat