Component grounding

Thanks for the helpful input. 

I introduced a 'new' integrated into my system and a hum appeared. In fact, I had owned this same model integrated about 10 years ago and seem to recall a hum at that time too. My tech friends assert that there are no technical defects, just something peculiar about the components' interaction. The hum goes away when I plug the amp into the second receptacle of the wall outlet, or when I use a cheater plug to connect it to the Shunyata. 

Ultimately I modified a power cord, disconnecting the ground wire. That took care of the hum, but then I began to worry that the amp was now ungrounded. So I installed a wire between the phono ground post and the grounding posts on the Shunyata. Maybe it's not necessary. 

@rfprice - that hum is probably due to the unit having a two pin plug OR being ungrounded.

This is common and easily remedied...

1. try connecting a piece of wire to the ground point on the power conditioner
2. then touch the other end to any unused RCA socket on your amp
3. the hum should disappear.

If it works you can make up a grounding lead as a more permanent solution using any old RCA plug, but connect to the neutral side of the RCA only

My NAIM amp was designed in such a way that it relies on the source components being grounded. So if the source had a two pin plug it would cause a hum

Hope that helps - Steve

@williewonka -- Thanks, Steve, I'll try that. The amp has a three-prong connection. Defeating the ground prong with the cheater plug made the hum go away.

Something funny happened yesterday. The integrated has a function that allows you to bypass the preamp section and use the output control on the source component instead (the DAC, in this case). I tried that for the first time yesterday and the hum came back. When I reengaged the preamp section, the hum went away again. 

@rfprice - you should NEVER defeat the ground on any component !!!

It is there for a reason - SAFETY !

I know its a common solution, but you are not addressing the root cause of the problem

Regards

@williewonka  -- Yes I know it's not an ideal solution.

I will try your suggestion to run the wire to the RCA terminal.