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Nordstrand NJ5FS in MIM Jazz Deluxe V - STILL BUZZES!!!!!!! >:|

Discussion in 'Pickups & Electronics [BG]' started by Moley13, Jun 2, 2014.


  1. OK.

    I've spent hours and hours shielding this thing, double checking continuity everywhere, ensuring solid grounding.......

    Then decided the pick-ups needed to go, and spent $300 on a set of Nordstrand split coils - supposedly hum cancelling. Just dropped them in and......

    THE B@$%^RD STILL HUMS (buzzes)!!!!!! WTH!!!!!!?

    Am I being extremely dumb or naive in thinking I can get a hum-free bass? Note: this is the kind of hum which is basically silent when facing one direction, but gets progressively louder turning 90 degrees.

    I'd even say with the Nordstrands in, the buzz/hum is broader spectrum (more trebles).

    I'm at a complete loss. HELP.
     
  2. xroads

    xroads

    Nov 6, 2012
    In principle, if you have 2 (passive) sc PUs in parallel, all turned up in volume, a Jazz bass should not hum.
    So, by replacing the PUs, you did not solve the root cause of the problem.
    Have you measured the resistance of your ground wiring (from the ground solder joints to the output)?
     
    Moley13 likes this.
  3. Exposed pole piece pickups will hum, or buzz, in certain situations no matter who makes them, or how much money you spend. If you get near any electromagnetic device such as a television or computer screen, or even yer own amp if it has a transformer, it will hum near it. Flourescent lights and light faders will also cause it. So will bad cables. I have had Spector basses wit EMGs hum. I've had Ken Smith an Modulus basses buz an hum, too. Not every night, but certainly in some rooms. It's the nature of the beast when usin magnets an electricity to make sound. Sometimes magnetic fields cross up. An cause hum.
     
    Moley13 likes this.
  4. Yes, negligible resistance from: pickup ground/copper plate behind pickup/all shielding (incl. pick-guard)/pots/bridge/strings/ground lug TO output jack shield.

    Interestingly, one of the pole pieces reads high (40 ohms) resistance, and several do not appear to have continuity at all.

    I thought the Nordys would at least be an improvement over stock. My (newer) stingray doesn't hum. Is that really the only difference though - you need to have those gigantic humbuckers to prevent hum?

    Thanks for the replies so far.
     
  5. No. I don't think so. The Stingray, bein single pickup, obviously has different challenges, tho it's exposed poles certainly will pick up room noise, too. I didn't mean that there wasn't somethin physically wrong in the wirin or pickups (grounding an shielding are frustrating), I just meant in some instances, any pickup can be made to hum, an that some guys too quickly blame the single coils, when they actually play near their computer screen, or amp, an get hum. My Fender American Deluxe 5 is a bass MANY complain about noise issues. Mine has none. No shielding or mods. Just quiet. But, in certain rooms? It buzzes. My EMG 35P loaded, fully shielded fretless does not hum in the same rooms, but on occasion exhibits noise wen plugged in. My amps contribute to this, too. Sometimes the room power is dirty, an there's nuttin you can do. My point was that tho pickups an shielding can help, that sometimes it's another issue. If those high end pickups still hummin? It prolly is somethin other than pickups. But, sometimes pickups are faulty out of the box. My procedure to check all this is very involved. Changin cables one at a time. Checkin all solder joints, shielding joints, and wiring paths. Then changin wall outlets, rooms, an turnin all fans off. Holdin my guitar, plugged in, an gettin near my rig. Roll one pickup off slightly, to see if hum gets worse, etc. I am sure you checked a lot of this, but I have had these maddenin issues before, an sometimes the issue was so simple, I missed it. The theory that two single coil pickups, both volumes at full, will cancel each others hum is sound. I'm jus runnin thru the issues I've had, an maybe will give clues or get yer mind thinkin in a direction other than just thinkin it is the pickups. Lots of contributors to noise. It is virtually impossible to eliminate every source. In every room. Every time. This stuff has a mind of its own on occasion. An can be quite frustratin.
     
    Moley13 likes this.
  6. Here's an mp3 of the noise (very high [digital] gain).

    I start with bridge soloed (I have a blend pot), then move to the middle - the noise decreases. The 50Hz hum (yep, 50 here) seems to VANISH as soon as the detent is reached. There's still some weird "buzz" much higher up. This buzz vanishes when moving to the neck pickup, but a little 50Hz comes back. Basically, the neck PU seems a LOT quieter than the bridge, which seems to be contributing not only "hum" but "buzz" (using TB convention of hum = mains, buzz = higher freq.).

    Please have a listen if you can.

    Does this point to possibly something being "injected" to the bridge PU? maybe a hot touching ground somewhere (I've checked, like, a bajillion times, though!).
     

    Attached Files:

  7. I would say ground hum coming from the mains in your house/rehearsal place/studio but after hearing the audio clip, I'm not so sure. There should be no/very little hum, no matter what the position of the blend since they are humbucking coils. Have you tried one pickup wired straight to the output jack, and see if that's quiet...
     
  8. Yeah, doesn't seem to change it. That was with alligator clips though, and I had the cavity open a little (compromising the shield somewhat) to do it.
     
  9. Hum that changes based on the orientation of the bass is indicative of EM radiation. Think of a sine wave at different degrees through its waveform. At 0 degrees its amplitude is minimized, while at 90 degrees its amplitude in maximized. This is what is happening to your bass. It is acting as an antenna and when you change orientation you are changing the phase relationship between your bass and the EM radiation. There are two things that can fix this. The first is to never play around anything that emits EM radiation, the second is to shield your pickups and control cavity.

    Sounds like you've already done the 2nd. I can only suggest that you make sure there are NO gaps in your shielding, as any gaps can still let in some EM bull poopie.

    edit: You can verify that you are picking up EM noise by hooking your pickups (old or new, they should have the same results based on your symptoms) to an amp while they are not installed in your bass. This way the bass is ruled out of the equation and you can determine the next course of action.
     
    Kael likes this.
  10. Thanks for that info.

    I can't quite work out the part about phase, though... I'd have thought a) the phase relationship is not important, any picked up fluctuating field regardless of phase would make the "same" (effectively) sound, and b) phase would change with the distance from the source, not the orientation.

    As far as I was aware, the orientation thing was because the effective area of the surface varies with angle, so the flux density changes. http://en.wikipedia.org/wiki/Flux <<< a few good diagrams there. You can see more through a window if you're looking directly at it (90 degrees), and you can see less and less (and eventually nothing) as you approach parallel to it.

    I'll try hooking up the old bridge pup and see what happens.

    Just to clarify, the sound that the BRIDGE pickup makes in the MP3 clip above is (anecdotally) is consistent in "tone" across locations, but does vary in volume (very loud in some rooms which also set off the guitarist, almost dead quiet in others). It's that upper, buzzy sound, not 50Hz hum (unless it's just the upper 50Hz overtones being greatly exaggerated somehow).
     
  11. BlueTalon

    BlueTalon Happy Cynic

    Mar 20, 2011
    Spokane, Washington
    Endorsing Artist: Turnstyle Switch
    The orientation can matter in the situation if your bass is acting like an antenna, kinda like a radar dish. Are you sure the pickups you put in are split-coil? Did you see the dual inline coils with your own eyes?

    You said, "Interestingly, one of the pole pieces reads high (40 ohms) resistance, and several do not appear to have continuity at all." That makes me think part of the problem could be the pickup itself. I have split-coil pickups in my avatar Jazz (Fender Super 55s), and they are dead silent, so I'm a big believer in the split-coil J pickup. But I'm also pretty fastidious about my shielding.

    I think you could have a grounding problem. I had a sound like that coming out of my bass one time at someone's house, it freaked me out because I thought there was something wrong with the bass. It turned out that house wiring at that outlet wasn't grounded -- it was an outlet for a three pronged plug, but the ground part of it wasn't connected. I plugged into a different outlet that was grounded, and the problem went away. So that might be something for you to check.
     
  12. I did eyeball the split coils (one coil over the lower three strings, one over the other two... is that right?). The pole piece grounding is done by Nordstrand... they just provide that grey wire (in addition to white/black) which is theoretically the "pickup ground" (rather than one end of the coil, which is referenced to ground through the black lead).

    ....Right?
     
  13. BlueTalon

    BlueTalon Happy Cynic

    Mar 20, 2011
    Spokane, Washington
    Endorsing Artist: Turnstyle Switch
    I've never seen the Nordy split-coil up close, but what I imagine you have is two pickup leads and a shield/ground lead, so I think you are right.

    Question: I have seen a picture of a Nordy 5-string split-coil J pickup with the cover off, and it was as you describe, one coil covering three strings and the other coil covering two strings. Do the neck and bridge pickups split the opposite way or the same way? In other words, is it

    BE ADG
    BEA DG

    or

    BE ADG
    BE ADG

    ?
     
  14. BlueTalon

    BlueTalon Happy Cynic

    Mar 20, 2011
    Spokane, Washington
    Endorsing Artist: Turnstyle Switch
    I missed this earlier. The resistance should read zero if the shielding is done correctly. So...

    Are the pickup cavities fully shielded, or is there just a plate at the bottom of it?
    Is the control cavity fully shielded?
    Are the wire channels between the pickups and the control cavity shielded?
    What does the shielding consist of?
    Is the bridge well grounded?
    Is there zero-ohm continuity between the bridge and the pickup cavities? Is there zero-ohm continuity between the shielding and the ground lug on the jack?
     
  15. Hmmmmm, I'm not sure, very good question. In any case, I'm basically ok with the neck pup and the "hum" cancelling with both on, seems to just be the bridge "buzzing".

    [in response to Nordy pickup design]
     
  16. Yes. (edit: yes, fully shielded, with a thick copper plate too)
    Yes.
    Not the bridge one - couldn't get into there, it's extremely narrow. Neck "channel" is basically the same cavity as control, and is shielded.
    Shielding is copper tape. Checked that the adhesive is conductive.
    Yes.
    The continuity between those points you mentioned (and others) never goes above 1.5ohm. Mostly less than 1ohm. I'm not convinced my multimeter is terribly accurate, though.
     
  17. Here are some sound samples of the old (Fender Noiseless Vintage) pickups outside the bass. The Neck pickup buzz decreased when I touched the pole pieces or the magnet underneath, the Bridge did the opposite. Both were sensitive to orientation. The buzz was definitely louder than when these pickups were installed, although the 50Hz hum seems around the same level.

    Any further suggestions? It's the BUZZ I'm really concerned about. Note that: Under the same conditions, my stingray (HH, 5 string) DOES NOT make this sound.

    P.S. - couldn't get the gain up as high as the last file, because of the "peaks" caused by touching the pups, but it IS louder than when installed.
     

    Attached Files:

    Last edited: Jun 3, 2014
  18. BlueTalon

    BlueTalon Happy Cynic

    Mar 20, 2011
    Spokane, Washington
    Endorsing Artist: Turnstyle Switch
    Have you contacted a local priest?
     
    Moley13 likes this.
  19. DiabolusInMusic

    DiabolusInMusic Functionless Art is Merely Tolerated Vandalism Supporting Member


    This is incorrect. Shielding will indicate resistance to show it is all connected.

    OP, do this simple test. Touch strings/metal/bridge and see if the hum is affected. If it goes away it is shielding, if it gets louder it is grounding, if it remains constant it is a deeper issue but I would check the ground at the bridge. If it remains constant it might just be 60 hz hum which requires humbuckers to remove (or 2 in-phase single coils.)

    I also do not shield the channels between routes. You can view my process/guide to see what I do, just check my submitted threads for one about hum.
     
  20. BlueTalon

    BlueTalon Happy Cynic

    Mar 20, 2011
    Spokane, Washington
    Endorsing Artist: Turnstyle Switch
    He already said it was around 1.5 ohms which is close enough to zero. You are incorrect, NO resistance shows it's all connected. Resistance means there's something in the way.

    I know you don't shield the wire channels, I read your thread. I think you are wrong, but I wasn't going to start a discussion about that in your thread. If you want to be thorough, why skip that part? You don't want to go to all the trouble of shielding everything else to eliminate noise, and then have a pickup wire acting like a little noise antenna in the non-shielded part. Besides, either way, you are going to have to electrically connect the shielding in the pickup route to the shielding in the control cavity.

    I'm a believer in overdoing things. There is a reason for triple redundancy in things like aircraft -- systems usually don't fail, but sometimes they do. I use copper tape for all the open surfaces. I use thin tape and many layers, and I solder most of the seems. I use copper tubing for the wire channels. They are taped and soldered at both ends, so it is airtight (or EM-tight). That should guarantee an electrical connection, but even so, I still run a ground wire from the shielding in the pickup routes to the shielding in the control cavity.

    I know you're a paint shielding guy. So use the damn paint! Use a Q-tip to slather the inside of the channel. Choosing not to shield the inside of the wire channel, when it's possible and easy to do, is just foolish IMO.

    And your touch test is kinda irrelevant. Once the decision is made to shield a bass, shielding and grounding become the same thing. All the inside surfaces need to be shielded, and all the shielding needs to be grounded. Of course, the bridge needs to be grounded too, and that's not really shielding per se, but it is grounded to the shielding (or should be).

    What I do for that is put the bridge in place and trace a light pencil line around it. Take the bridge off, and then I lay a flat even foundation of copper tape the same shape as the bridge but just a hair smaller. I solder the ground wire to the copper where the indent in the wood is, and then solder the other end to the shielding in the control cavity. I think the last time I did it, I used two wires, soldered to different places in the control cavity.

    The last step is to make sure the shielding is connected to the ground lug on the jack. My final check is to test the continuity between the remotest possible points, like between a saddle height adjustment screw and the far side wall of the pickup route and the edge of the jack outside the bass. Ideally, everything should read zero (or 1.5 ohms!). Once that is done, there will be no issue with shielding/grounding. If there is still an issue, it is with the pickups or the circuitry. Or the house wiring. Or the nearby power substation.
     

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