Phono hum....help needed

Discussion in 'Audio Hardware' started by Steve0, Mar 21, 2020.

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  1. Steve0

    Steve0 Audio Banana Thread Starter

    Location:
    australia
    I recently moved to a new house and have run into a problem with my phono....it hums and hums really bad.

    Phono stage is a Herron VTSP-2 and it worked fine prior to moving and also works fine at a friends home ( tested this week).

    Have tried it from power points downstairs and upstairs...all hum bad. Even with out the TT connected up it hums as soon as it comes out of warm up mode.

    I also tried cutting the earth pin off a cheap cord, no change, worse if anything. Its a very loud hum which makes playing LP's out of the question.....

    Gear listed in my profile..

    Any ideas what this could be and how to fix it?
     
  2. Glmoneydawg

    Glmoneydawg Forum Resident

    Location:
    Ontario Canada
    Have you tried reversing the position of that power cord you cut ground pin off of?
     
    The FRiNgE likes this.
  3. HiFi Guy

    HiFi Guy Forum Resident

    Location:
    Lakeland, FL
    Which table? The Thorens or the Rega?

    For the Thorens, I’ve had systems where a connected ground caused hum but it was silent without.

    Have you tried to connect the Thorens/SME ground cable to the amp as opposed to the phono stage? I’ve seen that work too.

    No clue on the Rega.
     
  4. Steve0

    Steve0 Audio Banana Thread Starter

    Location:
    australia

    It hums even with no TT connected....and hums with the rega connected or connected and turned off. the 124 is sleeping currently
     
  5. Benzion

    Benzion "Cogito, ergo sum" Forum Resident

    Location:
    Brooklyn, NY
    Try a power conditioner with EMI and RFI filtering. The issue must be with your electrical wiring, since it works in other places.
     
    Rick Bartlett likes this.
  6. Ontheone

    Ontheone Poorly Understood Member

    Location:
    Indianapolis
    Call Keith Herron. He will step you through some troubleshooting. It sounds like some filter caps went bad.
     
  7. Strat-Mangler

    Strat-Mangler Personal Survival Daily Record-Breaker

    Location:
    Toronto
    Before you do any of that, temporarily turn off all circuits except for the one used for the Herron. Does it still hum?

    Are you plugged directly into an outlet or into a power bar? If the latter, bypass it. Any change?
     
    The FRiNgE and Steve0 like this.
  8. leadear

    leadear Member

    Location:
    boise
    My TD124/SME3009 hummed too. I reversed the way the cord was plugged into the power strip and the hum decreased, but is still present.
     
  9. Steve0

    Steve0 Audio Banana Thread Starter

    Location:
    australia
    thanks for all your replies, I was not able to test out most of these ideas yesterday as I had to go help with a family matter. Will report back later today after I work my way through them.
     
    Strat-Mangler likes this.
  10. The FRiNgE

    The FRiNgE Forum Resident

    Look for sources of AC electromagnetic RFI, phone chargers, power supply for a laptop, doorbell transformer (directly under the floor will affect the audio gear) thermostat transformer, light dimmers, furnace control box, any device that contains a transformer. A street power transformer can cause hum. Have an electrician test the electrical panel grounding, water pipe ground and grounding rod, secure bonding. Another tip, connect all audio devices on the same outlet, or at least on the same AC leg. (ie: the same breaker would be the same leg) The single phase electrical panel has two legs, one the opposite phase (across both makes 240 volts) so if the equip is on two separate outlets, and the outlets are on the opposite phase, this can cause hum.
     
  11. Athalwolf

    Athalwolf Tu be or not tu be? That is the question.

    Is the hum in both channels?
     
    The FRiNgE likes this.
  12. Steve0

    Steve0 Audio Banana Thread Starter

    Location:
    australia
    Finally got around to trying to fix this...installed a proper earth stake into the ground...no fix..

    removed all other electrical fuses from main board so cut power to rest of the house- still hums....

    ran a dedicated lead up from a brand new air con cirucut installed 5 months ago--- still freakin hums....

    so it seems to be coming from the street source....

    Next up is getting the utility provider to test for a source.

    Phono worked fine at a freinds house 2 weeks ago as another test.

    FML.
     
  13. jupiterboy

    jupiterboy Forum Residue

    Location:
    Buffalo, NY
    Very frustrating. You might be able to look at the hum and determine what frequency it is at. That might give you a clue about the source.
     
    patient_ot likes this.
  14. Benzion

    Benzion "Cogito, ergo sum" Forum Resident

    Location:
    Brooklyn, NY
    The last fix I can suggest is a battery operated phono. I think Sutherland makes one, and some others. They run a pretty penny, but it will solve your hum problem by being independent of the power grid.

    Or alternatively, a big battery pack, suitable for audio, that you can plug your phono into. If it's only phono that you're going to plug into it, not the whole system, then you may get away with a relatively small one, and those could be had for a few hundred bucks.

    Edit: Sutherland Ph3D Phono Stage mm/mc Battery powered Shipping Free
     
  15. Strat-Mangler

    Strat-Mangler Personal Survival Daily Record-Breaker

    Location:
    Toronto
    You didn't try a cheater plug?
     
  16. Benzion

    Benzion "Cogito, ergo sum" Forum Resident

    Location:
    Brooklyn, NY
  17. G E

    G E Senior Member

    Are there any lights on the same circuit? Dimmers?

    what’s in the other side of the wall behind TT? Wall mounted plasma/tv? Something else with a large transformer?

    telecom or PC gear?

    Are your phono cables shielded?
     
    patient_ot likes this.
  18. FalseMetal666

    FalseMetal666 Forum Resident

    Location:
    Seattle, WA
  19. Vinyl Addict

    Vinyl Addict Forum Resident

    Location:
    MA
    How close is the phono to the turntable?
     
  20. Ontheone

    Ontheone Poorly Understood Member

    Location:
    Indianapolis
    May want to experiment with gear placement in your rack. Sometimes these high gain pieces of equipment develop hum when too close to transformers in amps/preamps etc. I had a wicked time figuring out a place on my rack for my SUT for example.
     
  21. psulioninks

    psulioninks Forum Resident

    Location:
    KC Chiefs Kingdom
  22. Gramps Tom

    Gramps Tom Forum Resident

    I am not an expert, yet it seems like there is a grounding issue of some kind.
    Like troubleshooting any problem. I have found it best to start by trying simple solutions.

    I have had tt based hum occur a few times in my life. The fixes included:

    #1 - Bad detachable headshell
    #2 - Bad mounting wires between cart & headshell
    #3 - Bad RCA cables between tt & amp
    #4 - Dimmer light switches on same electric circuit as outlet used for tt (prior to using circuit protector)
    #5 - Most recently, 2 months ago, a friend developed hum, and the problem was a cartridge that went bad internally. Cart mounted on non-detachable shell on tonearm. Replaced with new cart, and no hum at all. Did nothing else.

    Might be worthwhile to verify your cables are securely and correctly connected, and routed away from power cords as feasibly as possible.

    No doubt you've tried all these, but for others viewing this thread, the experience may help.

    You state the amp works in another setting, but did you take your turntable there, or just the amp and use his/her turntable? If just the amp, my guess the trouble is orginating somewhere in the turntable/cartridge.

    Also, does your main amp have a phono stage you can connect the tt through to discover if there is hum through it without the phono pre-amp?

    Or, perhaps try connecting the phono preamp through a different input source on your main receiver/preamp.

    All the best,
    GT
     
    Last edited: Apr 1, 2020
  23. Benzion

    Benzion "Cogito, ergo sum" Forum Resident

    Location:
    Brooklyn, NY
    Funny it's Jim Hagerman's article they're re-printing, as it is one of his units I'm currently having a hum issue with that's driving me nuts.
     
  24. Benzion

    Benzion "Cogito, ergo sum" Forum Resident

    Location:
    Brooklyn, NY
    Update

    I was able to further reduce the hum today from my Hagerman Cornet3 by placing a rubber foam sheet under the phono to isolate it from the metal surface of another component it sits on.

    Yet further improvement was achieved by slipping a strip of the same foam under the cables (RCA and ground) sticking out of the back panel, to make sure they also are not touching the metal of the component below.

    The hum is nearly gone now - inaudible at all unless I really put my ear to the speaker drivers, and even then quite faint.

    A big stone off my shoulders.
     
    mike catucci and G E like this.
  25. I have a friend who had a similar issue with an old Thorens easily solved:

    Get a ground-lift adapter: about $3

    Plug in the two-prong into the three-prong lift adapter and the hum should disappear. Try that before $$$ power conditioners, et al.

    Be well,

    Bill
     
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