Static/Noise


#1

I am having an issue with my DS and I am hoping someone might be able to offer some suggestions.

I am a long time PWD II user and recently upgraded to the DS via kit. My configuration had been: Olive 4HD to PWD II to Axiom Passive pre to D-Sonic M3 to Vapor Audio Cirrus speakers. My goal was to replace the PWD and passive pre with the DS and then eventually switch to an XLR connection. So my motive for upgrading was as much about the improved volume control as the updated DAC. I excitedly received the kit, did the upgrade and placed the DS into my system while removing the passive pre. I was immediately greeted with static, a ground loop hum, and a weird swirly noise. The swirly noise occurred regularly once every second and sounded like I was tuning a radio. I ripped apart my system and rebuilt it trying various combination of cables and layouts. My power cables are mostly Triode Wire labs with a Wireworld strip. My RCA digital cable is Analysis Plus and my interconnect and speaker cables are Grover Huffman. Eventually, I found a combination that worked. If I used a cheater plug on the DS and/or Olive and a toslink between the Olive and DS, I was only left with slight static that could only be heard with my ear to the speaker. This is not ideal, but manageable. I then replaced the RCA interconnect with an Antipodes XLR which allowed me to remove the cheater plug and go back to the RCA digital connection. I was happy with this solution because I had planned to go XLR anyway.

A month later, I started to hear the static again, but no ground loop hum. The static slowly increased over a week (it seems stable now) until I can hear the static from across the room. Music plays fine, but the static is still audible. The swirly noise is back but less that before and now at two second intervals. So, I ripped my system apart again without a solution. Then I replaced the DS with an old Cambridge Audio dacmagic and the system is quite. I did not play music with the dacmagic because it doesn’t have a volume control.

Any suggestions?

Thanks,

Briang


#2

Have you upgraded your DS software to at least 1.1.6?


#3

Thanks for the response.

I am now. I went from 1.1.2 to 1.1.5 and now 1.1.7 without a change.

Briang


#4

Briang, sorry for not being of great help with your hum issue. But just to let you know, my experience is exactly opposite. When I had the PWD MKII in my setup, there was a slight hum on the right channel, hearable from my listening seat with no music playing. The switch to the DS (also the kit) removed that hum completely. I don’t know why, because I always accused my pre to add the hum. When I connected the PWD directly to the amps, the hum was almost gone. I didn’t change the ICs nor the SCs, so it can’t be cable related.

I’m on FW 1.1.7, the pre and the amps are xlr-wired.


#5

I’d try reseating the ribbon cables, the power supply cable, and the fuses in your DS kit. If the hum and static remain, try running the DS with the cover off and gently wiggling cables and tapping boards to see if anything changes. Obviously, use your static strap and try avoid shorting anything out (like yourself).


#6

Do you also have the noise when you only connect your DS to your pre and poweramp? All other equipment like the olive should be disconnected for the test.

To prevent your system for ground loops and interference.

  1. Keep powercables close to each other. Different mains cables for your audio system have to go the same route through your home.

  2. The shield of powercords interconnects etc. should better be connected only at the source side of the cables.

  3. Phase out your equipment phase and neutral for every peace of equipment. This will prevent stray current through the interconnects.

  4. Keep powerlines and powercords far from interconnects even when they are shielded. Magnetism won’t be stopped by a shield.

  5. Get your mains checked for DC. Because DC will cause humm in your transformers.

  6. Disconnect the ground wire from your mains for a moment to check if it really is caused by ground noise.

  7. Disconnect the cable of your cable provider for a check. (Get a galvanic isolator plug)

Hope you will find a solution soon.