New cable with ground connection for a Sansui AU-717

[SansuiJavier]

I have a question, my Sansui AU-717, European multi-voltage version, comes (like most of Sansui) with two-wire cable, without grounding, and sometimes, depending on the position of the plug, I notice a small electric tingling, which It would be solved with a ground connection to the power grid of my house.

I have a 719, also a European version, which does have a ground connection, connected directly to the amplifier's mass (in the pic, the yellow wire to the transformer screw), I do not know if it was made by a previous owner or it came from the factory.


Can I replace the original 717 cable with a 3-wire cable with a ground connection? It comes from the factory without grounding for some reason or just because of the age of the amplifier?

Thanks for your help,

 

[Hyperion]

You can change the cable for a 3 core, and include an earth connection. I am not sure why (Sansui) gear from this era doesn't generally have an earth connection, but it is much safer to include one and might even result in a lowered noise floor.

The only caveat is that if another item in your system does have an earth connection, you might create a hum loop, but this is quite rare and easily remedied by re-arranging where the units are plugged into the mains, or by disconnecting one of the earths. But... make sure you know what you are doing if disconnecting any earth connection, and make sure to reconnect afterwards if it doesn't solve the problem.

 

[SansuiJavier]

You can change the cable for a 3 core, and include an earth connection. I am not sure why (Sansui) gear from this era doesn't generally have an earth connection, but it is much safer to include one and might even result in a lowered noise floor.

The only caveat is that if another item in your system does have an earth connection, you might create a hum loop, but this is quite rare and easily remedied by re-arranging where the units are plugged into the mains, or by disconnecting one of the earths. But... make sure you know what you are doing if disconnecting any earth connection, and make sure to reconnect afterwards if it doesn't solve the problem.

Thanks John, I'll keep it in mind. Virtually none of my equipment is grounded, not even the B-2102 or X-701, much more modern. I would never disconnect the earth from a device that carried it from the factory, for safety. I've done tests with the 717 and I do not have loops, even, as you say, the noise, especially in phono, is less present. Definitely, I'll change the cable to three wires with grounding.

 

[Hyperion]

I would never disconnect the earth from a device that carried it from the factory, for safety.

Spot on Javier, exactly right.