A good place to start would be to temporarily use a cheater plug to determine if you have a ground loop.
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Tonearm plugged into the phone stage = hum. Tonearm disconnected from phono stage = hum. Cheater plug added to power cord for phono stage = hum. Cheater plug added to power cord for preamp = hum. Connected the tonearm ground wire to the ground of the phone stage. (Phono stage manual recommends that) = hum. Grounded phono stage to ground of a few other pieces = hum.
RCA out from the preamp feeds a powered sub. Disconnected that cable from the input on the back of the sub just now, for giggles. Accidentally touched that rca tip to a screw/ground on the back of the sub (other end is still connected to the preamp rca out) and the hum essentially stopped. LOL
Everything was powered by the Furman...so I just ran a 50’ extension cord from the preamp to an outlet in the kitchen. Hum still there.
The fact that the hum went away when grounding the tip of an RCA, while the other end is plugged into an output on the preamp is strange.
@millercarbon I know from reading your posts for quite a while now that you’ll have some theory about this gremlin. ;) It’s quite vexing.
@hagtech I held the phono stage in the air, about 4 feet away from everything, didn’t help. Could be that I have no true ground, as you suggest. Interesting that the hum goes away when I touch the RCA tip from the preamp audio to a ground.
@cleeds The hum exists even with the cartridge not connected to the system, and issue has been there for a long time.
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.
@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 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.
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.
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.
Ran ground wire between grounding posts of the pre amp and the phono stage. No change. Only thing that removes the hum is to disconnect the audio cables between the phono stage and preamp, turn off the phono stage, or ground the tip of the other end of an RCA cable that is plugged into the pre amp’s audio out.
Update: after listening carefully, there are two different layers of noise. White noise hiss, and a 60hz hum. When I touch the RCA from the preamp out R to a ground, the hiss vanishes from the R speaker, but the hum remains.
Bought a new phono stage. Same exact behavior, but the hiss and hum are not as loud. I only get hiss and hum when I turn the preamp way up. Maybe this is normal, but the hiss disappearing when grounding that RCA tells me there may be a way to make it better. The hum is also annoying.
So, this happens with 2 diff makes/models of phono stages, using power from the power conditioner and from a separate socket doesn’t change anything. Also tried a cheater plug 50’ away, on a diff circuit. No help.
@hagtech I read your document, thanks. You’re saying hiss is “normal” and is “what we are trying to achieve.” The hiss I hear disappears when I touch the aforementioned RCA to a ground, which tells me maybe it can be eliminated(or at least mitigated) somehow. For the hum, I have already gone through all your recommended steps. So long as the phono stage is connected to the preamp, it generates hum regardless of my whether the tonearm cables are connected to it. Regardless of which of several outlets and power cables I use, or whether I isolate the phono stage by holding it in the air away from everything. Wave it around, and the hum is unchanged. Multiple phono stages, and different phono stages have different level of hum. Your PDF also suggests my problem may be too many grounds, hmm, not quite sure what to try next.
Don’t know if you solved the hum problem, hopefully you have and can point me in the right direction.
I just bought the Aria to match my Rega Planar 8 w/ Apheta 3 cartridge and get the hum issue too. So guess that eliminates your cartridge. My older preamp has MM/MC built in and when I use it with the turntable no hum, dead silence. I wanted the Aria for improved Sonics, brand matched so less problems (haha) and better loading for my cartridge.
I too have tried everything I can think of to no avail. Rega only points you back to the Rega reseller so I’ve reached out to them.
If I come across a solution I’ll post it here, unless you’ve solved your issue.
Hi I have an Aria Mk2 with exactly the same problem. After months of experimenting, swapping out different cartridges, cables, turntables and loaning various mains conditioners etc.nothing has worked for me. I thought I could live with it but hold on, why should I have to?
I’ve come to the conclusion there is an internal design or component mistake by Rega which is generating the noise. Yes I understand no stage is dead silent but too many people seem to have the same problem. So my question is does anyone have the same MC hum problem with the new Mk3 version? I understand its had an electronics tweak as well as a facelift.
Ultimately I’m going back to the dealer with my MK2 and will do a side by side comparison. If the MK3 shows no improvement with the MC hum noise, then I’m sorry Rega, as much as I love the sound of the Aria, this is a major design flaw and I’ll be buying a better one without the same problem.
Without listening to it yet I really hope the Mk3 steps up to the plate. If they have fixed the problem, then I shall remain a Rega owner.
Hi, I had similar problems when I switched from MM to MC, which is a bit like an antenna for stray noise. In my case, there is a nearby broadcast antenna that was generating RFI. The MMs weren't as susceptible to it. After trying most of the things you did, I started bringing home different phono stages. The one which rejected the noise, sounded amazing and met my budget was the Parasound Halo JC3 Junior. Dead black. Can even turn the volume way up with nothing playing an no hummers', hiss or anything else (not a useful test for listening to music, but proves how silent the Halo is).
As your own description suggests, it is not the MC cartridge that brings in RFI, it is the high gain phono stage required to amplify the signal from a low output MC that is often the culprit (or the RF can get in via your AC cord or the ICs from cartridge to phono inputs). You found a well designed one that does the trick.
@lewm , there is no doubt that high gain will magnify noise already present. My understanding, however, is that not all MC use a high permeability steel shell or other shielding to block or reduce rfi, and that therefore the cartridge can indeed be the culprit for the noise. As we (me and people who actually know this stuff, which I don't) ran different scenarios to rule out the etiology, it seemed the culprit was the MC itself.
As I have an extremely quiet electric system, with an independent breaker for audio, and no noise elsewhere at any volume levels, with speakers or headphones, it is hard for me to accept your diagnosis. That said, if you can explain your thesis more, I'd appreciate it, as I am always ready to discard my previous assumptions.
I have a Rega P8 going into an Aria MkII to a Pass Int 60. No hum. Even with volume turned up and just phono source selected, no record playing, its just soft white noise, no buzz or hum. The phono cables from the Aria to Int60 are 3 conductor, grounded at the source end (Aria), but left ungrounded at the amp end (Int60). Maybe you have a cable issue?