Persistent ground buzz
Printed From: Graham Slee Hifi System Components
Category: Turntable Audio
Forum Name: High Fidelity Turntable User
Forum Description: Technical Q&A, hints and tips
URL: https://www.hifisystemcomponents.com/forum/forum_posts.asp?TID=1385
Printed Date: 27 Mar 2026 at 6:08am
Software Version: Web Wiz Forums 12.01 - http://www.webwizforums.com
Topic: Persistent ground buzz
Posted By: suede
Subject: Persistent ground buzz
Date Posted: 05 Apr 2012 at 5:17pm
I have a very frustrating recurring problem with ground buzz. It's a fairly high frequency buzz and it is pretty silent but still quite annoying when listening to headphones. If I twirl and bend the mounted TT cables, which have the ground wire attached running along between the signal wires, I can momentarily remedy the problem but it usually comes back straight away. Sometimes though, it has fixed it for days or even weeks! While bending and twirling I get some sporadic static crackle in one or the other speaker. Is my mounted TT-interconnect bunk or how can I remedy this permanently? I would be very thankful for any answers or tips how to fix this!  Cheers! Johan |
Replies:
Posted By: Graham Slee
Date Posted: 05 Apr 2012 at 5:41pm
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We don't have a clue what arm, turntable, cartridge or interconnect you're talking about here suede. Please give us some details as well as some photo's including the arm base plug etc. ------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |
Posted By: suede
Date Posted: 05 Apr 2012 at 6:09pm
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Sorry! It's a Pro-ject Debut III Esprit turntable, the interconnects are factory mounted to the TT and hooked to my Reflex M, grounded correctly there of course, and the cartridge is an Ortofon OM40. The arm is the factory mounted standard that comes with the TT. I'm sorry I can't supply any more precise details, I had just hoped this was a well known problem with an easy solution regardless of the make or specs of the turntable. Also, I forgot to add in the earlier post that when I touch the Reflex and thus ground it through my physical self the problem ceases. Therefore I guess that I could perhaps fix it by connecting the Reflex ground post to that on my line amp, but would this be safe doing? I'm not quite versed enough when it comes to electronics to dare try this without someone who is saying so. Thanks for taking the time helping me out Graham! |
Posted By: Graham Slee
Date Posted: 06 Apr 2012 at 10:24am
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The ground post on your line amp, if it is a ground post, that is to say if it is connected to the case metal work, is OK/safe. However, it may or may not work. It does make me wonder if there is any ground continuity between arm "wand" and arm base on the Pro-Ject? In olden days arm manufacturers used 5 pieces of wire: 4 for signal connections to the cartridge and one to connect the "wand" to the arm base because the engineers of yesteryear had real brains... they knew arm bearings are poor electrical conductors and without the 5th wire eventually buzz would enter the equation. I'm not saying it's this. ------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |
Posted By: Fatmangolf
Date Posted: 06 Apr 2012 at 11:16am
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Hi Suede some practical tests you can do: 1) turn volume up so your HF buzz is clear 2) hold a metal part of the tone arm (e.g. the screws on the headshell) with one hand 3) touch the earth contact on the Reflex If 2) increases the buzz this reduces the buzz from 1), the arm is probably not well earthed or the earth cable is damaged, which fits with the crackle when twirling you described. If so replace the earth wire and see if that helps. From your message we know 3) is better than 1, so see if 2 plus 3 is better than 1. If the buzz is much lower there may be a problem with the arm earth connection in the TT. If not you may want to try connecting your line amp's chassis to earth e.g. a central heating pipe or the mains earth, this may have the same effect as your original check. The other thing I would investigate is the possible source if the interference. Is your TT next to mains cabling, lighting dimmers, anything with digital electronics in it, e.g. a CD player or satellite receiver or a set-top box? The cartridge or its cables are vulnerable to interference so just moving the TT may help. You could test this by carefully picking the TT up and moving it away by 40-50cm from wher it sits now, put the stylus protector and arm transport lock on first. Hope this helps. Jon ------------- Jon Open mind and ears whilst owning GSP Genera, Accession M, Accession MC, Elevator EXP, Solo ULDE, Proprius amps, Cusat50 cables, Lautus digital cable, Spatia cables and links, and a Majestic DAC. |
Posted By: tg [RIP]
Date Posted: 06 Apr 2012 at 11:27am
| A further thought, I have noticed similar symptoms to those described, when one or another of the phono plug/socket pairs were not making good contact. Not all socket and plug combinations will mate well together, some being a sloppy fit either on the ground connection (outer contact) or the inner socket. Pulling the plugs off one at a time may indicate which is the culprit, as may wriggling the plugs at the socket. I have a number of cables that will not make effective contact on certain items of equipment but are fine with many others. |
Posted By: suede
Date Posted: 08 Apr 2012 at 3:49pm
There are in fact 5 pieces of wire here. 4 for signal and one ground wire connected to a screw on the underside of the arm at the headshell end, just behind the cartridge and all its connectors/wires. And it does in fact seem to have been badly soldered to the spade on the screw and is now loose. It's impossibly thin, not much thicker than an eyelash, so it doesn't surprise me that it has come loose. It has a rubber "sock" or tube around the connection which before hid the bad connection. The wire does however stick to the old solder if I make it, very weakly but still. It fixes the problem so maybe I can live with this for now. The deeper buzz/hum I get when I happen to meddle with the cartridge connector wires, is that normal or is it due to the bad earth connection on the arm you'd say? Thanks for everyone's great help here! |
Graham Slee wrote:Posted By: Graham Slee
Date Posted: 08 Apr 2012 at 7:02pm
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If you touch the cartridge wires you will get lots of hum/buzz. That is because the phono stage is amplifying the electrical noise induced in your body from the many low frequency electro-magnetic fields surrounding you. The gain of a phono stage at mains frequencies is around 7 times more than the 1kHz reference frequency (roughly 850x). ------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |
Posted By: suede
Date Posted: 08 Apr 2012 at 7:20pm
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But these loud hums does not go away when I remove myself from the wires. I have to prod on them rearranging their fixations until they become quiet. And the hum can also appear if I happen to "drop" the tonearm onto the arm-lowering mechanism stand without being sufficiently gingerly for example. Just so that a slight vibration might occur in the arm. |
Posted By: Graham Slee
Date Posted: 08 Apr 2012 at 7:51pm
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Poor connections?
------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |
Posted By: suede
Date Posted: 08 Apr 2012 at 8:33pm
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Maybe it's as simple as tg suggested then? I could try clamping the connectors on the cartridge a little tighter with some small pliers. Maybe that'll do the trick? |
Posted By: Fatmangolf
Date Posted: 08 Apr 2012 at 8:33pm
Well spotted, I think that is probably the fault. The oud buzz when you tough the cartridge connections is not a problem as Graham has explained. If the TT is within warranty please take it back. Otherwise do you or a friend have a low wattage soldering iron and a delicate touch to resolder that ground wire to the arm? Jon ------------- Jon Open mind and ears whilst owning GSP Genera, Accession M, Accession MC, Elevator EXP, Solo ULDE, Proprius amps, Cusat50 cables, Lautus digital cable, Spatia cables and links, and a Majestic DAC. |
Posted By: suede
Date Posted: 08 Apr 2012 at 8:59pm
| I do still have warranty, it's just that I bought a demo showcase unit so this seems like too small a snag to return it for. And they will probably say I just caused the severage myself, why would I wait almost a year to return it otherwise |
Posted By: Fatmangolf
Date Posted: 08 Apr 2012 at 11:29pm
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Please ask them to replace this faulty piece of equipment. I respect your hesitance over the retailer's reaction. It is your right to buy a piece of reliable equipment with your hard earned money and their job to remedy a fault like this for you. Jon ------------- Jon Open mind and ears whilst owning GSP Genera, Accession M, Accession MC, Elevator EXP, Solo ULDE, Proprius amps, Cusat50 cables, Lautus digital cable, Spatia cables and links, and a Majestic DAC. |
Posted By: suede
Date Posted: 13 Apr 2012 at 4:47pm
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Thanks Jon for your concern, I will have a talk with them about it. But further, on the problem itself, a new twist in the tale has appeared. When I turned off my line amp yesterday (something I usually never do) and then turned it back on again it seems that the buzz has disappeared. I don't know for how long it will stay good, still I think it's bit strange Edit: Scratch that. The buzzing just reappeared and reattempting the little on/off-switching trick did not help this time. Guess I'll just have to go over to my local hifi store and be a bother. I'm sure they'll help though, they're always very friendly and not just in an oily salesman manner but genuinely so  |
Posted By: Fatmangolf
Date Posted: 14 Apr 2012 at 12:20am
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It's worth the effort and they seem good people who will want to get things right for you. ------------- Jon Open mind and ears whilst owning GSP Genera, Accession M, Accession MC, Elevator EXP, Solo ULDE, Proprius amps, Cusat50 cables, Lautus digital cable, Spatia cables and links, and a Majestic DAC. |
Posted By: suede
Date Posted: 17 Jun 2012 at 9:05pm
This thread is a bit old now perhaps but I thought I should give a quick update on things still. To extricate you from your sure to be sleepless nights.  I got my turntable back last week with the ground wire soldered back on. Then this week I went down to Southampton helping a friend sail a boat down to Dover and didn't have much time to check the turntable before. Anyway, home at last, when I was listening earlier today I realised something I hadn't before obvious though as it was. That the buzz didn't just come and go randomly like I had assumed but was only ever present at dusk or nighttime. This led me straight to the overlooked culprit, a light switch dimmer in the same room as the stereo.  Anyway, thank you all for your helpfulness and good tips! Johan |
Posted By: Fatmangolf
Date Posted: 17 Jun 2012 at 9:23pm
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1. LOL 2. Have you now fixed the dimmer? 3. Thank you. It is nice to know there is an answser to the mystery. ------------- Jon Open mind and ears whilst owning GSP Genera, Accession M, Accession MC, Elevator EXP, Solo ULDE, Proprius amps, Cusat50 cables, Lautus digital cable, Spatia cables and links, and a Majestic DAC. |
Posted By: suede
Date Posted: 17 Jun 2012 at 10:33pm
No, I haven't. I don't even know if it's fixable. I'm afraid dimmers are just dirty beings by nature spilling out their jumbled frequencies into the mains and the only way to fix it will be to redraw the lines and isolate the outlets used by the stereo. Or, infinitely simpler, just do away with the dimmer. However I don't want to do that either so for now I'll just have to do my listening in the dark  |
Posted By: tg [RIP]
Date Posted: 18 Jun 2012 at 2:57am
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Good to know you have traced the source of the problem. Perhaps the knowledge will benefit others having similar issues, thanks for following up. |
Posted By: Graham Slee
Date Posted: 18 Jun 2012 at 6:29pm
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Dimmer! Yes, I had exactly that problem 38 years ago. Such a long time that I'd forgotten all about it. Shucks! ------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |
Posted By: suede
Date Posted: 19 Jun 2012 at 12:56am
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Shame though, dimmers are handy things. But excellent sound knows no compromises. |
Posted By: Graham Slee
Date Posted: 19 Jun 2012 at 8:54am
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Dimmers work by shortening the mains frequency half cycle so that the power to the lamp is reduced. The circuit delays the switch-on by an amount programmed by the control knob -- it delays the gate signal to a bi-directional semiconductor switch called a Triac -- often a Diac, a bi-directional equivalent to a zener diode is placed in series to effect a voltage drop to the gate. Once the Triac gate voltage reaches the threshold set, it's gate "fires" the semiconductor switch, and rather than having the natural sinewave "ramp" over the 0.01 seconds of half cycle, the firing puts the full voltage to the load at a point part way through the half cycle. The light bulb filament is inductive and that tries to oppose the current driven into it. The result is "ringing" which although a snubber circuit is commonly used, still puts some spike onto the mains wiring. The instantaneous spike if repetitive -- i.e. a frequency -- will be at radio frequencies, and therefore highly transmissive. The mains wiring acts as transmitting aerial and the magnetic phono cartridge acts as receiving aerial due to its inductive properties. A series of spikes is received and amplified by the phono stage and corresponding system components. These are not however hum, but spikes which repeat at twice the mains frequency (100 or 120Hz). Some dimmers claim zero-crossing but the Triac inherently switches off at the zero crossing point awaiting its next trigger anyway. True zero crossing would lead to full-on all the time and no dimming. Some expensive dimmers provide a different solution where so many full half cycles are passed whilst some full half cycles are off. However, this type can look like the lamp is flickering, and if the flicker were to occur around 11Hz, it could trigger an epileptic fit in normally healthy people. The best solution is to use a combination of lower and higher powered lamps and switch to the lowest power when you require to be in dull lighting. ------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |
Posted By: suede
Date Posted: 19 Jun 2012 at 1:32pm
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Thank you for the highly detailed summary, very interesting and nice to know! But does this mean that isolating the mains used by the stereo better with its own fuses and whatnot will be done in vain as the cartridge is just picking up aerial interference? |
Posted By: Fatmangolf
Date Posted: 19 Jun 2012 at 3:12pm
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I have had the dimmer buzz problem in the past. In the last 25 years I went for two light fittings (ceiling lights for bright and low wattage wall uplighters or similar), which is similar to Graham's low/high wattage bulb solution.
------------- Jon Open mind and ears whilst owning GSP Genera, Accession M, Accession MC, Elevator EXP, Solo ULDE, Proprius amps, Cusat50 cables, Lautus digital cable, Spatia cables and links, and a Majestic DAC. |
Posted By: Graham Slee
Date Posted: 19 Jun 2012 at 5:12pm
In short: yes. ------------- That none should be able to park up and enjoy the view without a smartphone and the knowledge in how to use apps |
Posted By: suede
Date Posted: 19 Jun 2012 at 9:43pm
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Guess I'll just have to get rid of the dimmer then. I'm just glad to have found the source of the problem at last |