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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
 
Yah, I'm going to try the cheater plug and call it a day.  The return box is on deck and ready to shout it out.  

I've seen that the Parasound JC3+ (a bit more) and Jr (similar price to Aria) are well thought of phono stages.  Any other SS phonos I should look at in the 1500-2k price range (with all the performance of stages costing 10x as much, of course).  
sumadoggie's avatar
sumadoggie OP
62 posts
 
Interesting update: to further the notion that the Aria's hum is an issue of stray capacitance from my Hegel integrated and not a grounding issue, I took a longer set of RCAs (not high quality), and put the Aria on the floor blow my rack, maybe an extra five inches away, but also with another shelf in between it and the Hegel.  The hum got quieter again to the point where it was barely audible with my ear next to the speaker with the Hegel turned up proper loud.  

So, is a good-enough solution just longer interconnects and put the Aria on the floor?  
bill_k
936 posts
 
It's got nothing to do with "stray capacitance". Hum can result from the magnetic field of the Hegel's transformer being coupled to the Aria by induction when positioned too closely together. Increasing the physical space between them or changing their relative positioning will usually resolve the issue as you've found. If you have to use longer interconnects to achieve the required positioning it would be preferable to lengthen the Aria's output cables rather than the tonearm cables feeding the Aria's inputs.
yeti42's avatar
yeti42
287 posts
 
If you look at the power socket on the back of the Aria you may find it only has two pins, the one pictured on Regas web site does.
I don’t know recent Rega arms, my RB300 had a ground cable which grounded the mounting pillar but the actual ground for the arm is through one of the RCA outers, I forget which channel, there’s a soldered link inside the pillar. A rather odd arrangement and one I’ll revise if I ever use the arm again but with a Rega phonostage it should work with this setup. Ae you connecting a ground wire from from the deck to the ground post on the aria? Try removing it. Another test is to ground that post, if the amp has a ground post too that might be the best bet for that, assuming the amp isn’t double insulated too.
sumadoggie's avatar
sumadoggie OP
62 posts
 
Yah, I strayed from this forum and read an article from which I took that "stray capacitance" was an issue.  I now understand better that EMF from the Hegel's transformer is the problem.  The P10's RCA out would need a short extender to get the Aria to its current lowest noise position.  Since the interconnects I used to move the Aria to its current position are of the Radio Shack variety, I suspect an 6" extender on the Rega cord wouldn't degrade the signal.  

The Aria does only have two pins and the P10/RB3000 has no separate grounding wire to the Aria.  The Aria does have its own grounding post, though.  

At this point my plan is to distance the Aria from the Hegel as much as practical (under my component rack on the floor), which virtually eliminates the hum. Perhaps not an aesthetically perfect solution, but if it gets the job done without handing out more cash for a better shielded phono stage; or a "better" pre/amp set-up (god forbid.  I love my Hegel), then I'll be happy with the result.  It's the music that matters.  
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