[penguinpages]

Ok.  Have odd issue.  Yamaha receiver.  2 meter RCA output for front R /L that feeds to DSP that has 1/2 meter rca to tube amp.   I purchased high end cables.   And for almost two years I have had no issue.  But now I am getting crackle and slight hum.  Not 60hz hum.  As it has other fluctuations.   I have earth dedicated ground Rod for cabinet.  I baselines it down to cable from Receiver to DSP.   I changed cables as baseline but sound same.   It is not loud.  But ruins HiFi listening

I tried to research means to eliminate.   Moved cables.  Receiver. Etc.   it has slight effect but not perfect
What I did try and did work was to sheith the rca cable in aluminum branded cable

Tinned Copper Braid Ground Strap Wire Shielding EMI RFI ESD Protection Signal Screening Cable Sleeving Mesh (11/16 inch - 32ft) https://a.co/d/d9beBYW

This eliminates all adverse crackle /hum

Question:
1) as this is non ferromagnetic will it reduce the sensitivity of data signal in the RCA cable
2) are there other options or ideas to handle this kind of RF bleeding.  Or tool to find who is bleeeding. ( my guess is some dc/ac power brick or power supply is failing.  And is now putting out more RF   

[newzooreview]

It looks like you put your RCA cables inside this tinned copper sheathing from Amazon. I assume one sheath around each cable.

https://www.amazon.com/dp/B0B7RZQ8NG?th=1




An RF meter might pinpoint the source of RF interference. https://www.amazon.com/s?k=RF+EMI+meter&crid=1XU7N8BMCH632&sprefix=rf+emi+mete%2Caps%2C255&ref=nb_sb_noss_2

[penguinpages]

Any comments from technical perspective, will it interfere with the quality of signal from the receiver.

I know in signal aspect it has an effect on network cable signals if you band with ferromagnetic materials, but no clue on analog signal, and also at if copper eliminates that concern.

I will have to save some money and buy an RF scanner.   Do you have one you use / like.. that detects ranges that would effect audio signals. My guess is that it is more about the frequency on high end (above 100Hgz) but units I see on amazon are 10Mhz-8Ghz (10,000hz-8,000,000hz)   so Mhz-Ghz...  its off by a scale compared to listening ranges of 10Hz - 20Mhz (10Hz-20,000Hz)

[Speedskater]

For a US type AC power system.
First thing: Remove that earth dedicated ground Rod.
There must be only one connection point for all the building ground rods ant that is at the main breaker panel.
Make sure the all the Safety Ground wires are correctly connected.
Plug all the components into the same AC wall outlet.

[rollo]

   Have you checked the tubes in the Amp. Crackling sound may be a tube

charles

[circleman]

Congratulations on finding a fix!  Just out of curiosity, do you get the same issues if you go Yamaha outputs directly to tube amp, skipping the DSP?

[penguinpages]

It is 100% the RCA cable from receiver to the DSP.

If I unplug from DSP it stops

Once I put shielding on RCA cable..  noise stops.

I mostly need to know if that will create interference with signaling within RCA cable now that it is shielded.

[Speedskater]

If the RCA interconnect is a coax cable, will reduce interference and have no impact on the interconnects audio signal.

In fact Bruno Putzeys suggested:
Take a coaxial cable, take the jacket (sheath) off and dress it in a number of extra layers of shield braid salvaged from other cables. Hear the sound improve...