[kevin gilmore]

Its balanced.  The + input and the - input should both go to ground.
There are 500k resistors on board that do this, but the noise would
be much higher if the inputs are not tied to ground.

 

[HDMan]

Quote:

Its balanced.  The + input and the - input should both go to ground.
There are 500k resistors on board that do this, but the noise would
be much higher if the inputs are not tied to ground.

 
Grounding is ok, there is static like noise, it is quite though not loud. Yes the transformer noise is cut out when signal is passsing through, ground is taking effect.
 
Does this design use caps to eliminate DC offset noise from the inputs, or is that what the offset pot is for?
 
EDIT:
 
Switched RCA cables, static noise is gone. My RCA cables were not shielded.

 

[spritzer]

Just for the sake of clarity, the KGSSHV is fully DC coupled so the offset pot is there to trim the DC offset at the output.  Unlike dynamic transducers, excessive DC voltage will not destroy electrostatic drivers but it should be kept as low as it possible. 

 

[HDMan]

Want to buy my Khozmo for cheap? I am building the AMB instead.
 
http://www.head-fi.org/t/613653/khozmo-quad-attenuator

 

[gilency]

.

 

[gilency]

Well, Khozmo reimbursed me my money on their defective pot, no questions asked.
I was within 45 days of my Pay Pal purchase however and when he did not return my emails I opened a dispute.
He still did not answer and I escalated to a claim.
A few days later I got my money back.
The Goldpoint works great and I am quite content with the number of steps. With iTunes volume all the way up I then use the attenuator to control volume. No hum or hiss. 

Correction: there is noise with the attenuator all the way down, only in the first step. Not sure yet how to fix that since without grounding the pot I was unable to control the volume.
From step 2 to 23 is a noise free as it gets.

 

[HDMan]

Quote:

Correction: there is noise with the attenuator all the way down, only in the first step. Not sure yet how to fix that since without grounding the pot I was unable to control the volume.
From step 2 to 23 is a noise free as it gets.

 
I had the same problem at step 1, I fixed it by following Justin's instructions on another forum.
 

"XLR pin 1 should not be connected to star ground,  it should be connected to the chassis through the shortest path possible.  how you connect the chassis to circuit ground elsewhere is another story.

as for the metal body of the attenuator, i would have it conduct to the chassis and dont try to wire it anywhere."
 
So I grounded the XRL pin 1 to the XLR mounting screw, took the Khozmo star ground out of the loop and it is grounded directly by touching the chassis. This has worked for me, no more noise at zero volume and as quite as a mouse, completely black background even at full volume.

 

[gilency]

You meant Justin, right?
Thanks, I am planning on fixing it over the weekend.
My attenuator won't work without the ground leads connected though. Already tried that.

 

[HDMan]

Quote:

You meant Justin, right?
Thanks, I am planning on fixing it over the weekend.
My attenuator won't work without the ground leads connected though. Already tried that.

 
LOL, yeh Justin.

 

[gilency]

My transformer (SumR) began buzzing. The amp is otherwise working great.
I rechecked to make sure is well tightened to the chassis.
Is this a potential problem I should worry about?

 

[johnwmclean]

Are you using an SSR?

 

[gilency]

I am using the relay [size=9pt]G8P-1A2T-F-DC12[/size]

 

[johnwmclean]

I had a problem with a 25A ssr the transformer had a loud 50hz buzz, I switched to a 40A unit and the buzz instantly ceased.
 
http://relays.te.com/appnotes/app_pdfs/13c3206.pdf

 

[gilency]

Even with the transformer removed and connected directly it still buzzes though.

 

[johnwmclean]

1/2 wave halogen dimmers will cause dc in the line. Same with florescent lights. Switching power supplies on the same line as the audio transformer can cause dc disturbance.