Grounding problem with a dedicated line?

Discussion in 'Audio Hardware' started by DaveyF, Apr 5, 2019.

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  1. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif
    If the Esoteric is indeed the culprit, then I will find this out. Will report back.
     
  2. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif
    The culprit...and to those who were betting...

    Is the Esoteric SACD player!

    Once unplugged, the buzzing noise goes away. So now I need to figure out how to address this issue, anyone suggest an isolation device, or other, to deal with the ground connection issue with the player.

    I would rather not have to plug all the gear into the dedicated outlet, but that is still of course an option. Since I only have one dedicated line, it would seem all the gear on a power strip may not be ideal.
     
  3. jea48

    jea48 Forum Resident

    Location:
    Midwest, USA
    Dang it! I wished, or maybe know, did you ever notice the buzz with the mono amps and preamp powered on but with the SACD player turned off? I should have asked you to check that before completely unplugging the SACD player from the wall outlet.


    ***For preforming several on/off power tests.
    So as not to put stress on the mono amps, turning them on and off and then back on and off during testing you should be able leave the amps and preamp on by setting the preamp to mute, set the line-in input source switch to another input and then you should be able to turn off and on the SACD with out a transient voltage spike causing a loud pop or thud heard through the speakers.

    Test.
    For a test use a ground cheater on the Esoteric SACD player. Check for the buzz.

    ** But before you do. Is the power cord you are using on the SACD the factory OEM cord?
    Or is it an aftermarket power cord? If it is an aftermarket cord try using the OEM cord and then check for the buzz before installing the ground cheater.
    (This rules out the aftermarket power cord has the hot and neutral reversed at one end. Usually the mistake is at the IEC connector.)

    You need to buy one of these to check the AC polarity at both duplex outlets your equipment is plugged into.

    Receptacle Tester-400-029 - The Home Depot

    One other thing that might be worth checking is if the dedicated branch circuit and the convenience outlet branch circuit are feed from the same Line, Leg, in the electrical panel.
    If you can give me the circuit breaker numbers I can tell from the numbers. The numbers are stamped on the front of electrical panel cover.

    If the ground cheater doesn't stop the buzz then there is something else at play.

    .
     
  4. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif
    The buzzing is definitely caused by the Esoteric. I unplugged it and the buzzing went away. I also checked the polarity of the plug...it is correct. I tried a couple of different power cords on the Esoteric, both aftermarket and stock, no difference. The buzz goes away with the cheater plug on the Esoteric!
     
  5. Kyhl

    Kyhl On break

    Location:
    Savage
    What happens if you plug the Esoteric into the same dedicated outlet as the mono amps?
    What I'm hoping with this scenario is that the Esoteric grounds itself through the same ground as the amps, hopefully removing the hum problem.
    This might not help though if the ground issue is still leaking through the single ended outputs. Worth a shot.
     
  6. ghost rider

    ghost rider Forum Resident

    Location:
    Bentonville AR
    Maybe you should have mentioned you recently added the Esoteric in the OP. This thread would have been much shorter and you would have fixed the issue much sooner.
    Cheater plug is not the best long term solution it just points you in the right direction. Multiple post suggest plugging everything or at least the Esoteric into the dedicated outlet. Have you tried that? Different gear and how they engineer the grounds can be very problematic. I'm sure many can technically explain this, I'm not one of them.

    There is a long list of things to try google ground loops and start reading, plugging into the same circuit, grounding the chassis of the Esoteric to the preamp and possibly the amp might help. I'm guessing XLR ICs are not an option. and after you tried everything else one of these on the Esoteric might fix the issue. https://www.sweetwater.com/store/de...Y5pYa52ToyALzq5CFhXJZexZW5RE5dJAaAsJ_EALw_wcB
     
    F1nut likes this.
  7. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif

    I will try and run the Esoteric into the dedicated line. This isn't the easiest thing to do, as I have only one outlet....and the amps are mono blocks....so they require the whole outlet ( two plugs). I will need some kind of strip to do this. Will report back on that.
     
  8. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif

    Thanks for the link, that looks like what I need. As to grounding the SACD player to the preamp or amp...I tried that last night...no effect. XLR's are not an option.
     
  9. CoolJazz

    CoolJazz Forum Resident

    Location:
    Eastern Tennessee
    I'd bet a whole complete shiney nickel that the two circuits are not on the same leg of the power.

    Easy to blame the equipment and not focus on the real cause.

    CJ
     
  10. ghost rider

    ghost rider Forum Resident

    Location:
    Bentonville AR
    For testing if not a permanent fix.
    Accu-Cable EC3FER Edison Tri-Tap Power Adapter | Full Compass Systems
     
  11. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif
    I suspect you are correct. However, that doesn’t really explain the fact that the other gear on the second circuit doesn’t show this problem...and my prior DAC/ transport didn’t either. What do we think accounts for this?
    Nonetheless, it will be instructive to see what happens when I plug the SACD player into the dedicated line. I’m hoping that solves the problem...or a purchase of the hum killer that ghost rider linked to.
     
  12. CoolJazz

    CoolJazz Forum Resident

    Location:
    Eastern Tennessee
    Why the one piece of equipment does and another doesn't probably boils down to the circuit topology used in each. DC coupled equipment will try to equalize the difference between the two legs of the AC. Passing considerable current in some cases. In those types of cases then the buzz can come and go as loads come on and off changing the potential difference between them.

    Always the circuits used on a system are best when from the same source, let alone from the same leg at least. Running a home run power feed doesn't and shouldn't preclude adding a very small additional pull from the front end equipment. It's such a small pull and it really is much better than having it on a separate circuit where who knows what else is there?

    And while worrying about noise on electrical, call a hazmat team in and get rid of all the bad news expensive light bulbs that cause so much noise on the circuits. Long live the 98 cent bulbs! If your wife screwed in a hazmat bulb, while you were at work, at about the same time you bought new equipment....buzzzzzz. :nyah:

    CJ
     
    Doctor Fine and F1nut like this.
  13. Ralph Karsten

    Ralph Karsten Forum Resident

    Location:
    St. Paul MN
    This isn't hard to suss out.

    The problem is two-fold at least- it takes two to tango. IOW you need two things that are susceptible to a ground loop in order to get a ground loop- hence lifting the ground at the amps worked. The CAT has a decent grounding scheme and so the amps can be grounded using that and yet no ground loop. But hook up the Sony, which has a poor grounding scheme and you have a problem.

    The amps are inappropriately grounded. Sorry, but in this matter despite being nice sounding amps Jadis didn't know what they were doing. You ran into this because the chassis of the amps and the circuit ground of the amps are the same thing. You can verify this with a DVM on the Ohms scale- by measuring between the RCA input ground and chassis you will see a dead short- and also to the ground pin of the AC power cord. Same with the SACD. When the latter was plugged into the CAT, it shorted the CAT's grounding system out (without damaging it) because its RCAs were now connected to chassis via the AC power cord of the SACD. Ground Loops bonanza!

    There are several solutions- fix the SACD player or fix the amps. In either case it would be to separate the circuit grounds from the chassis and install a resistance so the circuit ground floats at chassis potential. But that probably isn't practical- Sony isn't going to fix this and I doubt very much that Jadis could.

    So you have to go with plan B which is to isolate the outputs of the SACD by using a set of transformers to isolate the ground of the RCA output of the SACD. You can get them from Jensen transformers. This is the one you want: CI-2RR | Jensen Transformers

    OR- you could continue to run the ground cheaters but put it on the SACD rather than the amps and be aware that a fire hazard is present should something Bad happen. On account of the latter, this is not recommended.
     
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  14. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif
    Thanks for the suggestions, Ralph. I like the idea of the Jensen transformer, although I am not terribly enamored of having to add another ic. Nonetheless, seems like a decent option.

    I am a little surprised that the amps...and particularly the Esoteric SACD player (not Sony), has a poor grounding scheme. It would seem that job #1 would be to take care of a detail like that!!
     
  15. harby

    harby Forum Resident

    Location:
    Portland, OR, USA
    "Boutique" often means "out of the garage of someone who also makes dubious claims counter to basic principles of electrical science". Within three posts of looking for a schematic for you, I found "Jadis amplifiers are notoriously poorly designed (performance and reliability)"

    Anyway, where could the design be causing these problems? It is not, as above, simply that the RCA ground is the same as chassis ground - that's how almost all audio components work.

    The power supply of a Jadis JA80:

    [​IMG]

    See all those grounds after rectification on multiple windings, the ground at the center tap I point at. When the diodes have non-identical voltage drop or noise because of the transients from the voltage drop, it is dumped to ground. When the bottom winding is uneven, the center is not 0V and that AC is dumped to ground.

    What about an Emotiva could also give you problems? No circuit diagrams, so we just have to look at a typical one, since there's no model number given in this thread. See anything wrong?:

    [​IMG]

    Where's the friggin ground wire?? Similarly, after the filter board, a multitap toridial transformer, that may be dumping an AC potential into a center tap with nowhere to leave but the signal ground.

    The more you pay, the less you get, not just in value, but often generally. We need to disclaim the "Best CD transport under $10,000" threads early.
     
    ghost rider likes this.
  16. ishmael

    ishmael Forum Resident

    I think the best and easiest, but maybe not the cheapest solution is to purchase a good power conditioner/ isolation transformer. You will
    get isolation and clean AC. Win Win.
     
    DaveyF likes this.
  17. ghost rider

    ghost rider Forum Resident

    Location:
    Bentonville AR
    Davey's must not be like because using a cheater plug on the fixed the hum. On that unit a cheater would do nothing. Nice job on digging up enough evidence to show what we might like to thick is quality gear is just as likely have plenty of short-comings.
     
  18. Bill Hart

    Bill Hart Forum Resident

    Location:
    Austin
    That won't fix this problem, i have had the same issue with my Lamm ML2 SET amps. I have a 10kVA isolation transformer (it weighs around 400 lbs) and dedicated lines. It's an issue having to do with how the chassis ground and signal ground are wired in the amps. I think Ralph nailed it, and Harby's been on the case.
     
  19. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif
    I’m not qualified to talk about the internals of this gear. However, I do think that the Esoteric is exceptionally well made...(no clue about emotiva? ) . I seriously doubt that the Jadis is at fault here.. as I now know that the Esoteric is the cause of the buzzing...and not any other piece of gear in my system. ( including the Jadis mono amps).
    All kinds of gear can apparently develop and lead to ground loops...which would then beg the question....why don’t all of these manufacturers insure that this is unlikely to occur.
    Ralph, can you assure us that none of your amps or preamps have ever been the cause of a ground loop hum or buzz?
     
  20. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif
    Bill, it seems that are no two manufacturing companies that wire the same way when it comes to chassis ground and signal ground.
    OTOH, My gut tells me my problem has to do with an imbalance between the voltages at the dedicated line and the convenience line.
    I going to try and plug everything into the dedicated line and see if that solves the problem.
     
    ishmael likes this.
  21. ishmael

    ishmael Forum Resident

    Understood. I am just wondering if he installs such a unit and runs it off the one dedicated line if that would help
     
  22. ishmael

    ishmael Forum Resident

    I think you may be on to something...please proceed and report back. :cool:
     
  23. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif
    I was wondering about that before this issue even began. I have a friend who swears by his PC and thinks it helps even when using a dedicated line. I have heard from several designers not to do that ( they say plug mono amps only directly into the wall!), but now that I have this grounding issue, it probably makes even more sense.
     
  24. CoolJazz

    CoolJazz Forum Resident

    Location:
    Eastern Tennessee
    Ralph's pre's haven't in my system! Well manored and awesome sounding! And I don't expect any issues running balanced and not sharing grounds.

    CJ
     
  25. DaveyF

    DaveyF Forum Resident Thread Starter

    Location:
    La Jolla, Calif
    That’s good, but I don’t think balanced is always the answer. My preamp is single ended only. Interestingly the Esoteric does have the option to go balanced, but CAT puts her claws out.
     
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