My turntable has only RCA outputs (no XLR support) that cannot be detached from the unit. I am designing a fully balanced phono stage that works both with MM and MC cartridges, with a variable load feature for universal cartridge support.
An RCA cable has a hot and screen. The screen is a heavy duty shield that encircles the hot and connects to ground. If I treat the RCA cables as balanced cable the shield would become hot. XLR connecters have two hots and a shield.
Will hum be picked up since there will be no shield if I use an RCA cable as a balanced transmission line?
It seems like it would not because the hum would have to not be common to both hots. Anyone have experience with this?
Also I am concerned about capacitance since the cartridge I am using is a Shure MM with a 47k impedance.
An RCA cable has a hot and screen. The screen is a heavy duty shield that encircles the hot and connects to ground. If I treat the RCA cables as balanced cable the shield would become hot. XLR connecters have two hots and a shield.
Will hum be picked up since there will be no shield if I use an RCA cable as a balanced transmission line?
It seems like it would not because the hum would have to not be common to both hots. Anyone have experience with this?
Also I am concerned about capacitance since the cartridge I am using is a Shure MM with a 47k impedance.