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Phono stage hum - Rega Aria

Hi folks, trying to solve a hum issue and would appreciate any thoughts. Rega Aria phono stage, into a PrimaLuna Dialogue tube preamp, then to Bel Canto SS mono's. 

With the tonearm NOT plugged into the phono stage, there's a hum.(especially when set to MC vs. MM)
Rega powered off, no hum while preamp at max volume. Turn the phono stage on, there's the hum...I hold the phono stage in the air, 4 feet from everything, same hum. When I hover it over my preamp, the hum gets much louder due to interference. Magnaplanar 1.7i speakers very quiet until that phono stage enters the chain.

Haven't tried a cheater plug...but have tried 2 diff interconnects (Better Cables/Silver Serpent and BJC LC1) from the phono stage to the PrimaLuna, and 2 different power cables (Furutech FP-S022N and factory cable) into a Furman Elite 15-DMi. 

Either this Rega Aria is a noisy phono stage, or I've somehow got a ground loop in there with it. It's really not bad at lower volumes, but sucks when that hum breaks the silence at louder volumes between songs/sides. 
Opinion - is this phono stage a weak link in my system? Maybe it would be fine if I find a way to eliminate that hum. 

JA Michell Gyro TT
Rega RB 808 tonearm
Ortofon Cadenza Black cart
Primaluna Dialogue Premium preamp
Rega Aria phono stage
Bel Canto M500 mono amps
Furman Elite 15-DMi power
Magnaplanar 1.7i

Better Cables/Silver Serpent interconnects
Blue Jean Cables for phono and Maggies
Furutech FP-S022N power/outlet

Cheers, thanks for any advice! 
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cleeds
5,640 posts
 
malmc02
The hum exists even with the cartridge not connected to the system ...
That really doesn't matter. Have you tried a cartridge other than the Ortofon Cadenza Black? You need to rule out the cartridge as a source of the hum, and merely testing the phono preamp with no load attached doesn't satisfy that.
... and issue has been there for a long time.
But: Was this issue always there? Did you previously get satisfactory results? That is the million dollar question.
malmc02's avatar
malmc02 OP
30 posts
 
@cleeds prior to the Cadenza, I was using an Ortofon 2m bronze, and had hum at loud volumes. I cannot ever recall a time in the past when I have turned the volume to a high level and not heard the hum. Having said that, I don’t often go to high volumes, so it wasn’t at the top of my list of priorities until being isolated at home in these crazy times, and I find myself with more time on my hands. ;). 
hagtech
163 posts
 
Yeah, you need to get an Earth ground somewhere in the system.  Touching RCA is a dead giveaway...
malmc02's avatar
malmc02 OP
30 posts
 
@hagtech tested my outlet with a multimeter, seems to be properly grounded. Don’t know if it’s an earth ground, but juice flows freely into it. The screw on the outlet plate is likewise grounded. Connected the grounding post from the preamp to the screw = hum. Moved the ground wire from the screw to the grounding post of the phono stage = hum. Ugh.
Yeah, it sure sounds like a grounding issue but not sure what to try next to get those rogue electrons out of the system. 
hagtech
163 posts
 
Something isn't getting a ground.  Use your fingers again.  If touching RCA shields lowers the hum, then you're on the right track.  Is there a power transformer near the tonearm?  What happens if you change MC loading to 47k, does it change to just hiss?  If so, then you have magnetic induction into the phono cable itself.  Offending source must be moved.

Use fingers to touch all "grounded" spots, including chassis metal, tonearm, ground lugs, etc.  Find out where you can make a difference.
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