Why use ground wire from preamp to amp???


I am buying new cables from amplifier surgery guys in downers grove, IL.  

The cables are nice looking, shielded, silver solder, cardas connectors silver plated, all silver solder used, silver tinned strands,Yatta  Yatta  Yatta, ok whatever,  


Their reference rca's come with the third ground wire? They said hook it to the preamp ground?

 This is not for phono connection, why would anyone hook a ground wire to preamp when not using the turntable?  I have never heard of this before, would this be dangerous, if some current or noise is sent down the ground wire directly into the cables at the input of the amp??  

Why even have them?? What is the purpose, or have I been out of the game too long?

shouldnt I just order regular reference rca's without that silly third ground wire which serves no purpose unless hooked up to a turntable???

HELP ME UNDERSTAND, PLEASE



128x128arcticdeth

Showing 1 response by williewonka

Arcticdeth - rprince is correct - they are using the ground lead to ensure upstream source components do not cause hum.

Case in point - I had a Pioneer ELITE DVD player and a NAIM amp.

NAIM’s "architecture" assumes that all SOURCES are correctly grounded to the mains ground

The Pioneer however was "isolated" - it only had a two pin plug - and when used with the NAIM caused a loud hum. Measuring voltage between the chassis of the Pioneer and the mains ground  with a multi-meter I was surprised to find a potential of 2 volts. 

Grounding the chassis eliminated the hum completely.

Since several of todays source components (like DACs or Phono Stages) come with either USB power or Wal-wart power supplies they can often be the source of "noise".

At one point in time - all of my sources had isolated power supplies - so I implemented my own chassis grounding scheme - just to ensure it was as quiet as I could get it. 

It does no harm to your components to implement this type of scheme - but if your components are correctly grounded it is not required. 

I prefer to connect each "isolated source" to a central "grounding point" that connects directly to the ground of the power supply and not "daisy chain" it via other components.

I now have source components that are properly grounded so I no longer use this grounding scheme

Regards...