Cyclops physical proximity to other devices matters

Placement of the cyclops matters (at least for my rig it does). I had it sitting on the PS-100 and it causes a low frequency hum to come through the amp. I lift it off and the hum stops. All the cables are evidence audio solid core, so I don’t think it’d be a cabling issue.

He’s a link to a video in dropbox to demonstrate the hum (if the video doesn’t play, right click to get the video URL)

Hi @lakeside

This is an example of a great questions!

My guess would be the proximity causes a form of coupling. It sounds like power supply noise gets into the signal?

  • Does changing where on the top surface change the hum.
  • If you unplug the power from the Cyclops change any thing?

Regards

Dan

Hey Dan.

Changing where it’s on the surface of the PS-100 makes very little difference. In fact, I used to have it to the left of my Axe-FX and it was making the hum too, so it’s not PS-100 specific.

If I unplug it, it still makes the hum as well. On my rig, it’s only when I move the cyclops away from all other electronic devices does the hum go away.

I posted another short video demo …

Hi Lakeside,

Thanks so much again for the extremely helpful videos!

I have a hypothesis brewing –

  • Still hums when power is disconnected from the Cyclops
  • Hum goes away when Cyclops is moved upwards - away from the Power Station
  • Hum gets a little worse when moved forward

I think this energy from the PS-100’s linear power supply getting coupled into the single ended cables.

  • Improves when cables are moved away from the PS-100
  • Occurs even if the Cyclops is off (because energy is entering the signal path magnetically
  • Gets worse when more length of cables covers the PS-100’s top surface.

If this is right you really only have two options:

  1. Space - move the sensitive audio cables away from the top surface
  2. Shielding - put the cables in a Faraday cage: metal foil (or mesh) this must be ground at one end.

Fancy testing this? I guess by moving the cables as far from the PS-100 as possible and keeping the Cyclops in place? Or you can get the tin foil out.

Regards,

Dan

Hi Dan,

I’d actually tried the tin foil a couple days ago and it made no difference, however, I hadn’t grounded the foil. How would I go about grounding the tin foil?

I won’t be able to test it for about a week (vacation!), but when I get back I’ll give it a go.

Alex

Hi Alex,

OK, do try bending the signal cables first as if this changes nothing then the shielding won’t work either.

I would try put the signal cables in a cable tidy/sleeve/conduit

put the cables inside then wrap it with an EMI or aluminium tape,

For example,

The foil tape should connect to metal shell of one of the jack plugs that are grounded.

However, before all that effort, maybe picking a different location would be easier.

If don’t have a cyclops, so I cannot test this , but I should probably order one.

Regards,

Dan

Hi Dan.

Moving locations is not an option. I’ve got a dedicated circuit for my rig installed and it’s not a portable rig.

I’m determined to get to the bottom of this. I’ve got on order RF EMI Shielding Tape SHIELD WRAP™ Nickel-Copper (NI/CU) 2.000" and some Expandable Braided Sleeving. Both should arrive in about a week or so.

You can see that the cables are spaced quite far apart. Can I assume that I am to try to loom together the first 6 cables from the left side of the cyclops (not bothering with the remote or power cable). In that case the shielding wrap will not go all the way to the cable plugs, or is there something else you had in mind?

Alex

Hey Alex, yes, I think that makes sense: you want to shield the line level and guitar level carrying cables from any stray magnetic fields from the power station and associated cables.

I’m really curious to see how things go! Fingers crossed we see an improvement :face_with_spiral_eyes: