2. analog
  3. 156664-112802

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! 
128x128malmc02
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.
smatsui
166 posts
 
Is your WIFI router or booster close to your components?  If so, unplug it and see if the hum goes away.  I had an issue with a WIFI extender that was too close to my vacuum tube preamp.  I've also had problems with WIFI boosters that use the electrical lines behind walls to extend the WIFI signal.  After I moved my extender away from my preamp, the hum went away.  Try it, it's an easy thing to do.
mijostyn's avatar
mijostyn
8,156 posts
 
The phono amp does not like your preamp for some reason. See if you can borrow another make or model to try. It could also be a defective phono amp but it is most definitely the phono amp. 
More to discover