Mains (?) noise

Sorry if this has appeared before (I’m sure it must have); I did try a search but couldn’t find a match for my specific issue.

I have a noise problem that seems to be coming from the bass itself. I got bass and amplifier whilst I was working away from home and staying in a caravan. There was a little noise then but definitely worse now I’m home. So some details:

  1. Definitely coming from the bass. If I unplug from the bass there’s no noise (so long as my hand is nowhere near the cable’s bare contacts.
  2. Same issue if connected to the bass or going through pre amp into studio speakers.
  3. Same issue with different cable (both reasonable quality Fender cables).
  4. The noise sounds like a mains hum but harsher, more noisy, rather than the pure sine wave normal mains hum.
  5. As I move around the room the noise comes and goes. Now the weird bit; if I move the bass from a normal vertical orientation to a flat horizontal position the noise also comes and goes. Though not consistently; sometimes noisy flat, sometimes noisy vertical.
  6. There’s a fair bit of electrical kit in the room; computers, monitors, hard drives, bass amp, studio monitors. The usual array of stuff.

I guess it’s going to be either a screening issue or an earthing one. I would be grateful for any suggestions.

Edit: Ah I just noticed something else. The bass is an Ibanez Mezzo SRMD200D which has jazz (bridge) and precision (neck) pickups with a control to swing between the two. If I turn it all the way to the P pups it’s perfectly silent but on the jazz pups it’s noisy but still comes and goes as I move the bass position.

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Where is your computer, tv, or other electrical device in the room? Wifi router, etc.

This is normal, welcome to playing in isolation with no background noise or other instruments.

Some basses are grounded/shielded better than others, pickups same. Active basses are worse mainly. So are cheaper basses. You can shield and ground better (see other threads here) but your environment and electronics quality matters.


Thanks for the response. Here’s a photo showing most of the electronics in the room (along with all my mess; I’m not the tidiest of people). The router/wifi is just behind the amp.

These are the pickups:

If I crank it all the way to the neck P pickups it’s completely silent but crank back to the bridge J pickups and they seem to be the source of the noise. It is an active bass and I guess a cheaper one just under £300.

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sounds like shielding would definitely help a lot like @John_E mentioned. you can get copper tape cheap (£10 or so) - just make sure it is listed as “conductive on both sides” or “conductive adhesive” or something to that effect such as:


So further investigation suggests it’s definitely the bridge pickup. I unscrewed the pickup and then moved it around (as mush as the lead lets me) and sure enough the noise comes and goes as I move it. The electronics cavity has shielding paint as does the pickup cavity and both have wires well screwed into it. With the electronics cavity open and all plugged in there is no noise caused by gentle prodding and pulling, so I don’t think there are any dodgy connections. It just seems to be that bridge pickup.

Is it worth looking at warranty or is it just something I’ll have to live with; like stand farther away from other electronics when using that pickup?

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Here you go:


Single-coil pups, i.e., many Jazz-style pups, are inherently prone to being noisy.


From my picture above, I assumed these are twin coil; appear to be two pickups per string on both the neck precision style and the bridge jazz one.

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The round metal circles you refer to are called poles, not pickups.

The entire assembly encased in black is the pickup.

The J-style pickup is a single coil type. The P-style pickup is a split coil type.

The split coil pickup design cancels out any noisiness (typically a hum sound); the single coil pickup doesn’t have the capability to cancel inherent noisiness.

Humbucker pickups are yet another design that purposely eliminates any hum, hence, its name.


Ok thanks, I guess the jazz pickup will only be useable in low EM environments then; as it stands it’s not really useable in my normal playing space. Oh Well!

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This illustration shows the various parts of a pickup. While this example shows a pickup for a six-string electric guitar, the principle design elements apply to a bass pup as well.

The cylindrical magnets are the poles.


Do any lights in that room use a dimmer switch or any kind of special controls?

Especially when there’s only one of them. The bridge J pup on my trbx174 is noisy too but I rarely use it :slight_smile:

Stacked single coil pups are a good solution though some people don’t like the tone as much and replacing a regular single coil might require some modification of the routing.

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Often cheaper pickups are not internally grounded properly and will pick up room noise, of which you have a lot, just like I do (most of us actually now with all the electronics). As others have said, jazz pickups are inherently noisy. There are designs that cancel the noise, Fender calls them ‘noiseless’ but it changes the tone they have as well. Others add a ‘dummy coil’ in the pickup to cancel the noise. I bet if you boost the treble you get more noise too, right? Welcome to the world of single coil J pickups and rooms full of electronics.


If you do want to change pickups, which is easy, it looks to me that the bridge pickup on your bass is a short Jazz pickup. Jazz pickups come in two sizes, a longer one which is always at the bridge, and a shorter one which is generally at the neck, but on select PJ bases the shorter one can be at the bridge.

I think the Ibanez Mezzo is one of those basses and Talkbass seems to agree with my assessment; I rely on them as much is I do Wiki, which is not at all. So by all means measure before you buy (if you buy).

A lot of folk roll all the way on the P, but I tend to keep the J/P ratio about 10% J / 90% P. Which to me is the sweet spot for PJ tone


I think your main problem is that you don’t have enough power bars / power strips (for the UK types) on your window sill above the radiator. There looks room for at least one more no?

My Jazz bass is noisier than my P Bass because of the reasons @MikeC explained above. So I mainly play my P Bass as it’s quieter. Also I prefer the sound of my P Bass.

I really wouldn’t lose much sleep over it. Turn down your single coil, turn up your split coil; then crank your nice new Ampeg Rocket amp and all your problems will melt anyway in a lovely wall of bass sound.


Absolutely. It all makes sense now and, to be honest, is pretty much as suspected. Might have to consider replacement in the future.

Yes and if I set mine at about the same then almost all the noise has gone. However, whilst I do like the rounded tone of the precisions I also like the punchier jazz despite having a little less sustain. Not unsurprisingly I find it works better for a more jazz like piece, like walking bass lines.

To be fair it’s not as bad as it looks; there’re a bunch of extenders just stashed there and not plugged in. But what can I do? It’s an old house and is rather lacking in power points. (In the kitchen if I have the kettle and the toaster going together and then use anything else it will pop the fuse).

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