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Isolating Digital Noise, need help.

I'm hearing noise from my ARC CDP thru my speakers presenting as a high frequency "whine" or "soft screeching." I need to isolate my digital from the AC line it shares with my analogue components. Running another dedicated line is not an option at this time.

I was wondering if a power strip with isolated receptacles, such as star-grounding, would be an alternative to a separate AC line.
As a test, I now have the CDP connected to a different outlet in my house and the noise thru my system is eliminated.

Would this type of power strip be an effective solution, and if so, I could use some recommendations. I have several layers of Blue Circle power conditioning, so I would need a strip with surge/EMF/RFI protection.
128x128lowrider57
lowrider57's avatar
lowrider57 OP
5,417 posts
 
@jea48,
What does the meter indicate when both test probes are touched against one another? "L"? There in as "short" or "000.0", continuity?
touching probes together shows 000.0 continuity.

I made a mistake, it always indicates "0L" when there is no reading.
I downloaded the manual for the meter.
https://equus.com/Content/Support/Manual/93-0041.pdf

What I want to know are the plug to IEC pin out connections
for the aftermarket power cord, the same as the ARC stock power cord?
the same.

To be 100% clear here, you did say the ground loop hum is being caused when only the preamp amp and amp are connected together by ICs. Is that correct? The CDP is not in the ground loop, possibly being the culprit causing the ground loop hum, correct?
Correct. CDP is not connected to inputs.

You said earlier when you used the stock cord that came with the CDP the high frequency "whine" sound was gone. Where was the CDP fed from then? I guess I was under the impression it was plugged in the audio system wall outlet when you switched to the stock power cord.
Yes, the stock PC was connected to the wall behind the system.
jea48
4,425 posts
 

Lowrider57 said:
I did some tests on the amp. With my multi meter, measuring from the male ground pin on the Sunfire amp to the metal chassis of the amp, I could not get a reading of resistance. The meter indicated “L.”

So "OL" equals open? Same as the meter reads with the probes not connected to anything?

Check again for resistance from the ground pin on the power cord plug to the metal chassis of the amp.  "OL"?

Next measure from the ground pin on the plug to one of the outer grounds of one of the RCA jacks on the back of the amp. (No ICs connected to the inputs of the amp.) Any resistance? "OL" ?

What is the model number of the amp? Do you have a wiring schematic diagram for the amp?

lowrider57's avatar
lowrider57 OP
5,417 posts
 
I hooked up the Pangea PC to the ARC CDP and I'm getting the same high-pitched noise as with the Audience cable.
 After several A/B tests, there is noise when using the stock PC, but less audible than with aftermarket cables.

So it leaves me to wonder if I should try an isolated power strip. Right now all my components run thru the Blue Circle and then to a Furman EMF/RFI strip except for the amp. Or is there a filter or power cord for digital devices?

tbg
5,263 posts
 
Do you get any noise when only the amp is in the system and on, of course?

jond's avatar
jond
5,807 posts
 
Is it possible to try a different outlet without the extension cord?
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