EMG jazz pickups and 60 cycle hum

narud · #1 02-01-2013, 09:12 PM

so i just installed some emg's in my main jazz that has a 2 band stingray preamp in it. tone is great. however i cant get rid of 60 cycle hum. its definitely not any type of ground buzz. if i point my bass in just the right location the hum will stop, but the majority of locations sound like a single coil being solo'd regardless of pickups settings. any ideas?

narud · #2 02-03-2013, 05:48 PM

20db pad · #3 02-03-2013, 06:19 PM

How old of a Stingray pre? Maybe there's some componentry that has aged beyond normal use life? I imagine you have already grounded both the pre and the EMG pickups, even though EMGs don't typically need grounding.

narud · #4 02-03-2013, 06:24 PM

Quote:

Originally Posted by 20db pad

How old of a Stingray pre? Maybe there's some componentry that has aged beyond normal use life? I imagine you have already grounded both the pre and the EMG pickups, even though EMGs don't typically need grounding.

ive got the same issue even with the pickups wired up to the supplied passive tone control. ive done multiple combinations of grounds, but im not getting ground buzz in the first place. its definitely 60 cycle hum. ive got an email out to emg but it was friday night when i sent it out so hopefully something will get sorted out. the tone is great and id really love to be able to use these pickups.

Stone Soup · #5 02-03-2013, 06:34 PM

Are the EMG's active or passive? If the noise disappears when you turn, isn't that a shielding issue? That shouldn't be a problem with active pickups.

narud · #6 02-03-2013, 06:41 PM

Quote:

Originally Posted by Stone Soup

Are the EMG's active or passive? If the noise disappears when you turn, isn't that a shielding issue? That shouldn't be a problem with active pickups.

standard set of active/stacked coil emgs. when i have ground issues with a bass (which i have in the past

) the buzz is there regardless of position and isnt directional. my single coil jazz basses hum louder when i face my amp if a pickup is solo'd. these emgs do the same thing and it doesnt matter if theyre solod or both dimed.

Stone Soup · #7 02-03-2013, 06:50 PM

Curious. I could only guess it has to do with the preamp. I have EMG's in my P/J, but no preamp and they're silent. Sorry I don't have an answer.

I'm interested in the solution EMG gives you. Subscribed.

57P · #8 02-03-2013, 06:52 PM

Did you use the output jack already in the bass or install the one that came with EMGs? And, are you sure the jack is wired correctly?

narud · #9 02-03-2013, 06:58 PM

Quote:

Originally Posted by 57P

Did you use the output jack already in the bass or install the one that came with EMGs? And, are you sure the jack is wired correctly?

both jacks. used the previously functioning jack and the quick connects with the supplied jack.

narud · #10 02-03-2013, 06:59 PM

Quote:

Originally Posted by Stone Soup

Curious. I could only guess it has to do with the preamp. I have EMG's in my P/J, but no preamp and they're silent. Sorry I don't have an answer.

I'm interested in the solution EMG gives you. Subscribed.

i pulled the pre from the bass and have the same issue with the supplied tone control. im interested in what emg has to say too

joelb79 · #11 02-03-2013, 09:32 PM

I have heard from Roger Sadosky posts here on talkbass that even on some EMG installs he has had to shield the bass and ground the strings before they were noiseless. He used to not connect the strings to ground because EMG suggested not to do this, but once the ground was replaced the noise went away and those basses were dead silent. Did you remove the ground wire to the strings?

narud · #12 02-03-2013, 09:56 PM

Quote:

Originally Posted by joelb79

I have heard from Roger Sadosky posts here on talkbass that even on some EMG installs he has had to shield the bass and ground the strings before they were noiseless. He used to not connect the strings to ground because EMG suggested not to do this, but once the ground was replaced the noise went away and those basses were dead silent. Did you remove the ground wire to the strings?

i went through and read all that stuff too. removed ground wire, reattached ground wire, tried grounding the pre to different spots, changed how the cavities were connected etc. nothing. i can understand grounding helping noise, but this doesnt sound anything like ground induced buzz. its single coil hum. im starting to regret not just buying some dimarzios. i got seduced by listening to alex al clips.

DiabolusInMusic · #13 02-03-2013, 10:11 PM

If you touch metal/strings/bridge and the noise goes away you have a shielding problem.

Just give the bass a proper shielding job and your hum will go away.

Ensure you line the inside of the pickup covers (if possible) with copper foil tape and ground the foil from inside the covers to the foil lining the control cavity. Also ensure you do the pickguard and every bit of the body cavity. You can source copper foil tape locally at stained glass supply shops.

I have never had hum I couldn't remove. You can quiet those puppies.

joelb79 · #14 02-03-2013, 10:22 PM

Quote:

Originally Posted by narud

i went through and read all that stuff too. removed ground wire, reattached ground wire, tried grounding the pre to different spots, changed how the cavities were connected etc. nothing. i can understand grounding helping noise, but this doesnt sound anything like ground induced buzz. its single coil hum. im starting to regret not just buying some dimarzios. i got seduced by listening to alex al clips.

You wouldn't happen to have clips of Alex Al playing EMG pickups would you? That would be great, I just saw a few clips of him and he smokes. None with EMG pickups though.

Perhaps this is a problem with the way the preamp loads the pickups. If the input impedance is wrong that can induce tons of noise that acts this very same way. You might have to load the preamp with a capacitor before the preamp.

What Musicman 2 band preamp? The self built uncle fluffy ones? Do you use the pickups included volume knobs before going into the preamp? Or any kind of blend knob or how is the wiring done? perhaps the problem lies in there. Also, X or normal J's. The preamp on the pickup might play into this, as EMG's have very different output impedance between the X and Non-X lines.

narud · #15 02-03-2013, 10:24 PM

thanks for all the suggestions guys, but i cant stress this enough, this is not ground induced buzz. its 60 cycle hum. it sounds just like a bass with standard singles except they dont hum cancel when both pickups are dimed.

DiabolusInMusic · #16 02-03-2013, 10:26 PM

If you touch metal/strings/bridge and the noise goes away you have a shielding problem.

If If you touch metal/strings/bridge and the noise gets louder you have a grounding problem.

This sounds like a shielding issue to me.

narud · #17 02-03-2013, 10:26 PM

Quote:

Originally Posted by joelb79

You wouldn't happen to have clips of Alex Al playing EMG pickups would you? That would be great, I just saw a few clips of him and he smokes. None with EMG pickups though.

Perhaps this is a problem with the way the preamp loads the pickups. If the input impedance is wrong that can induce tons of noise that acts this very same way. You might have to load the preamp with a capacitor before the preamp.

What Musicman 2 band preamp? The self built uncle fluffy ones? Do you use the pickups included volume knobs before going into the preamp? Or any kind of blend knob or how is the wiring done? perhaps the problem lies in there. Also, X or normal J's. The preamp on the pickup might play into this, as EMG's have very different output impedance between the X and Non-X lines.

im having this issue with the standard vol,vol,tone setup with the emgs as well. its not a preamp interaction thing.

its the homebrew uncle fluffy boards. it operates and wires up just like any other pre. its got an input and an output to the jack. you just put the two volumes before the input of the pre.

i think i just went trolling youtube for the alex al stuff.

narud · #18 02-03-2013, 10:27 PM

Quote:

Originally Posted by DiabolusInMusic

If you touch metal/strings/bridge and the noise goes away you have a shielding problem.

If If you touch metal/strings/bridge and the noise gets louder you have a grounding problem.

This sounds like a shielding issue to me.

none of these are the situation thats occuring.

joelb79 · #19 02-03-2013, 10:29 PM

PCBs for DIY clone 2-band Preamps

Your solution is here.

"and wire a 25k resistor from the preamp's output to ground." and use the EMG volume pots, remove the preamp's volume pot.

Edit: just read your post about both EMG volume pots and the preamp. It sounds to me like the pickups might be faulty as they shouldn't be doing this at all.. Have you talked to EMG about the noise using their pots?

narud · #20 02-03-2013, 10:34 PM

Quote:

Originally Posted by joelb79

PCBs for DIY clone 2-band Preamps

Your solution is here.

"and wire a 25k resistor from the preamp's output to ground." and use the EMG volume pots, remove the preamp's volume pot.

thats not the issue. the 25k resistor is there to simulate the 25k vol put that usually comes after the preamps output and before the jack since you usually wire a stingray pickup directly into the input of the pre. im already using the emg vol pots before the input of the pre. ive been using this pre in multiple jazz basses for a long time now with no problems.