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Rega Planar 10/Aria MC Phono Stage HUM

Hey all. I recently took delivery of a Rega Planar 10 and Aria Phono Stage. Hooked it up yesterday. Result: pretty significant MC hum. I’ve done some interwebbing on the matter and have seen the P8/Aria post at this forum, and see that the Aria seems to hum quite a bit. Most of the suggestions about fixing the issue are directed towards checking for grounding issues, etc. The rest of my system is fairly straightforward (Hegel H160 integrated; Hegel CDP4A; top shelf Supra wire) so after hooking it all up, I unhooked everything except the Aria to the amp and the speakers. Same hum, same volume. I did typical ground checks and that doesn’t seem to be the issue. I took the Aria and put it one more shelf away from the amp (as far away as the cable allows) and lo and behold the hum volume was cut in half. While at the new position, the hum would be "tolerable" at any particular music volume, it’s annoying when there’s no music signal going to the speakers. Standard light background white noise is somewhat expected, extraneous signal hum doesn’t work for me. So, if, indeed, this is a simple proximity issue (I don’t feel like buying more wire and putting the Aria across the room), is there an elegant shielding solution for the Aria? Is this an issue of Aria design (possibly an engineering "compromise" as Roy Gandy might suggest)? What are other phono stages at a similar price point ($1500ish) which perform musically as well as the Aria? I see I see the Parasound JC3 Jr might be an option. Looking forward to suggestions. Thanks!
sumadoggie
sumadoggie's avatar
sumadoggie OP
62 posts
 
While I don't have a frequency meter, and don't know if it's 60 or 120, it's certainly a hum tone.  

Should the wall outlet screw be grounded?  There are Faraday cages on Amazon in which the Aria would fit and when slightly modified the cables could be accommodated.  While cutting a hole for cables isn't ideal, perhaps that's a way to go.  

I did order some isolating fabric which arrives today.  I'll update the thread with my findings.  
sumadoggie's avatar
sumadoggie OP
62 posts
 
By the way, there is a "grounding post" on the back of the Aria.  Is this just there if the Aria is used with a different TT to prevent a ground loop, or can this post be used to help ground the Aria itself?
millercarbon's avatar
millercarbon
12,531 posts
 
Thanks for the DM. One key to preventing hum is having only one path to ground that is the same for everything. The Aria is already connected to ground via its power cord. So you connect the turntable to the ground on the Aria, and nothing else connects to that ground unless its another turntable. 

If the integrated is between the turntable and the phono stage then the phono lead has to go past it and there's a small chance it picks up hum along the way. Fooling around with phono lead routing is always a good idea. You can sometimes hear noises come and go while you're moving it, touching it, etc.  

Also, fields coming out of the integrated aren't necessarily equal in all directions, nor is the phono stage equally shielded from all directions. So there's always the chance that above it picks up noise, below it doesn't. Tracking these things down is my least favorite thing about phono, and explains why if you ever hear my system as totally to die for awesome as it sounds when playing music it would drive some guys absolutely crazy when its not. My standard is if the noise level is only about as much as groove noise then you call it good enough and get onto something else. You'll get there. 
smatsui
184 posts
 
I experienced no hum when I had the Aria and the RP10/Apheta 2 MC cartridge. Since then, I've upgraded my RP10 to the Planar 10 and Apheta 3 and I've upgraded the Aria to a Luxman EQ-500, again no hum.  I think the Aria is a good value phono stage but the Luxman is quite a bit better as it should be for the higher cost.  My vacuum tube Luxman produces less hiss (almost non-existant) than the Aria at high volume levels.
lewm
13,631 posts
 
If what you have with the Aria is truly "hum", then I am beginning to doubt it's due to EMI, but your story certainly is consistent with airborne interference, which usually is EMI or RFI.  Except you've now revealed that you had no hum with your old turntable and phono cartridge.  The problem arose when you substituted one Rega TT for another.  Was the Aria situated as close to your integrated amp back then, as it is now?  If so, the information about re-positioning the Aria in your room having solved the problem to some degree, is out the window.  And I am getting more convinced the problem is or was due to grounding. Either your components are grounded to two or more different nodes, such that ground in one case is a few volts different from ground in another case (a ground loop, in other words), or something just isn't properly grounded.

But have we all been through a a time warp in the last 24 hours since your OP?  You say now that you upgraded the Aria to a Luxman (which is indeed an excellent unit) and your problem is solved.  When did you go out and buy the Luxman?
And yes, the ground lug on the back of the Aria certainly is for grounding. Millercarbon mentioned that the Aria should be grounded to house AC ground via its power cord, but that assumes you are using an IEC standard, 3-conductor power cord and that your electrical outlets are properly grounded.  If you have an older home, that isn't always a valid assumption.
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