AC filter help with single coil noise .. is there any?

June 13th, 2005, 08:48 PM
With all the hi-tech gadgets to hit the market, it would seem like (by now) that someone would have designed some sort of a alternating current (AC) filter that could be used between the wall outlet and the guitar amp power cord.

I have crappy wiring at my apartment. I also have only one outlet to choose from. Also, if I move around in the room, I can find a "sweet spot" location in the room where I can actually stand and get less hum/noise from my favorite single coil babies. It sure would be nice to sit on the couch for a change...

I have all but given up on the concept of recording. It seems like the noise level is too high.

So, you see I'm sort of boxed in... I've already tried different amps, and different guitars, and different guitars thru different amps. It is always the same, single coil noise bugging me to death.... An American Telecaster, G&L ASAT III... not cheap guitars, either. Plus, a MESA/Boogie and an Evans Custom Amplifiers amp... not cheap amps, either...

There must be a solution for this other than swapping out my PUPs for some fancy new brand, or changing to a humbucker guitar.

Is there a line filter that will help out on the noise AT THE WALL OUTLET. With all the computerized, technologically advanced stuff out there and available today, I have a hunch there "must be" something.


I know they have line filters and surge suppressors (which are different) and battery back-up units (different still) for computers. These folks that play computer games and such want the cleanest, purest power coming into their latest processor... well, I need some help with my Tele's and Strat's to... I need and want the cleanest, purest power feeding my tube amp.

Another thought I had was... well, what do they do in a recording studio? Every artist that has ever picked up a single-coil guitar has plugged in to an amp in a studio, and...well, I don't hear this stuff on any CDs (the pickup noise that is).

I'm convinced the answer for me is to try for some type of line filter that plugs in to the wall outlet, and then I plug my amplifier into the line filter.

There is stuff out there for computers, but I haven't bought one just to experiment.

I thought it was a good topic for discussion, so I posted it here.

So, ya'll got any ideas?



John Thigpen
June 13th, 2005, 10:06 PM
I don't know of any filter like you're looking for, but you might check the various electrical lighting, appliances etc in your house and see if there are some that cause particular problems. I had a house that was particularly noisy, and found that if I turned the the power to the TV/stereo off at the wall (no playing along with CD's or videos, though), turned off the flourescent kitchen light, and turned off the dining room dimmer, my guitar would get pretty quiet. It wasn't the wiring so much as what was connected to the wiring.


Dave Brophy
June 13th, 2005, 10:26 PM
I saw what you're describing in a catalog a year or two ago.A new product.I lost interest when I saw the $200 price tag.I don't know what it's called,try a Google search with various words.
What happens when you use a ground lift?
I'd probably move the couch to the sweet spot and call it Feng Shui.

June 13th, 2005, 10:38 PM
Good topic there JamHandy.

The problem is not with the AC line voltage. If it were, a properly working amp would make noise with no input signal (guitar not plugged in). You can try that for yourself to prove the point. If the amp hums with no guitar plugged in, then you probably have bad filter caps in the amp. You amp by design already has the ultimate line filter, it is the storage caps after the rectifier. It is so good that it fills in the voltage between cycles when there is little voltage present.

Guitar pickups are designed to pickup varing magnetic fields, and those fields are all around us. The amplitude of the pickup of a magnetic varing field is proportional to the rate of change. Therefore, the devices that have fast rates of change of current draw from the AC line are the biggest culprits. This include the following:

Light Dimmers
Fluorescent lights
Neon Lights
Transformers - all kinds - power transformers in amplifiers, walwarts and etc.
Electric motors

If devices had a rate of change of current that was strictly a pure AC sinewave (like an incandescent bulb), all our picked up noise would be a dull HUM. Yet, we get this harsh BUZZ that contain all the fast edges of current changes and their associated harmonics.

There have been a lot of controversial posts on this forum and everywhere else about guitar shielding. Shielding of guitar cavities can help some, but it is by NO means the panacea for eliminating buzz. The only time I have ever had shielding help is when volume pots are wired backwards like a Les Paul or the Brent mason Tele. The cord to the amp goes high impedance when the pot is turned down, so cavity shielding is very helpful there. Think of it as a guitar cord unplugged from the guitar with a few inches of wire on the tip end.

You bring up a great point about studio recording with regard to buzz. First of all, good studios do not have the culprit devices listed above. They use incandescent lighting only with no dimmers (or if they do they are darn good dimmers). Also, as you have noticed, there is a "sweet spot" whereby rotating the guitar will minimize the buzz pickup. This is because the magnetic lines of flux around the pickup go to near zero at some point. Now, if all the buzz source came from one place and one field polarization, finding a low pickup sweet spot would be a chinch. Since there are usually several culprit sources, you can't completely position the guitar to get zero pickup. Studio players have always used the positional trick. Some have also reduced buzz by attaching a ground wire from their guitar and a ground source. Most likely, if this works well the guitar was not wired correctly anyway. Every situation is different.

I've always dreaded dealing with the stage hum. That's why I go with noise cancelling pickups (like Seymour Duncan Stacks). Some folks don't like them, and they are not as bright and "zingy" as single coils. I simply adjust my treble up accordingly. I always have plenty to spare.

I once had a guitar pickup on a broomstick, connected to an amp. I used it as a Geiger counter type troubleshooting tool to find unknown culprits. I'm glad in today's world I have replacements for my single coils and I don't need to worry about that anymore.

Let me end by saying that the stacks will pickup BUZZ if strong enough. I have 12 fluorescent bulbs in my workshop. The guitars I build with stacks will pick that up. I almost never have a problem on stage. Stacks and humbuckers are not perfectly quiet.

June 13th, 2005, 11:01 PM
Great question and not an unusual situation. If you're getting it from that fabulolus G&L / Boogie setup, you may have what was happening to me. I play upstairs, and that is where it would happen. Since I never played downstairs or out, I didn't realize the "why" so soon. I finally figured out that if there was any signal coming to a tv in the house, I got it. It was worse if I happened to be watching an instructional video with the vcr AND the tv on. I find that when the tv and vcr are off upstairs and down, I just don't get it at all. It would be worth it to notice if the neighbors are away whether you get it. It may be interference coming from the unit next door, above, or below

Good luck. I'm looking forward to reading other posts about this maddening mess.

June 13th, 2005, 11:13 PM
Great explanation, Terry!

Do you have any idea how a noise- suppression pedal, like the Boss NS-2, would work on pickup buzz? I played in a church a couple weeks ago, and the stage hum was terrible, the worst I've ever experienced... even in the hum-cancelling switch positions!

June 13th, 2005, 11:19 PM
I forgot to add the television to the list of culprits. It is one of the worst of all. There is a set of magnetic coils around the picture tube that deflect the cathode ray tube beam up/down and left/right to creat the picture. It just so happens that the vertical scan frequency is 60Hz, so the deflection yoke alone is a 60Hz (plus many harmonics) generator of BUZZZZ. The horizontal deflection rate is 15.75kHz, which is above what most of us can hear.

Thanks for mentioning the other culprit.

June 13th, 2005, 11:34 PM
Good question JH, and great answer Terry, you truly are the thinking man's chicken picker, that's a post for the archives (do we have archives here?) if there ever was one.

Had an outdoor picnic gig last summer and I bought a solid state battery powered amp just for the occassion. When I got home, I had this brilliant idea that the direct current from the batteries would give me pure, untainted hum-free juice for my telecaster.

Plugged in and was really shocked to discover that the buzz was as loud as ever- I had been so sure that the old wiring in my apartment was the culprit all these years..

I haven't been working much lately and I have noticed that there's definitely less hum during the day when everybodies out. It starts to get bad around 4PM when the first few people come home and turn on their radios and maybe pre-heat the oven for supper. It continues to build as TVs and computers get turned on and by 8 O'clock it's just unbearable and I have to pack it in.

Like you say, Mr. Downs, we're surrounded by magnetic currents and radio waves and there isn't much we can do about it. I have shielded most of my guitars, tho', and it does work to some extent. Better on some guitars than others, and I can't for the life of me figure that one out (Terry? maybe you could shed some more light here?).

Anyway, I took the money I'd been saving for a good power conditioner and bought some Kinmans for my thinline. That's become my favorite guitar.

June 13th, 2005, 11:45 PM
The NS-2 is just a noise gate like most others. If the input signal is below a presettable threshold, it mutes the signal. As soon as you play a note, the signal comes through with all the hum you had before. "Suppression" is not a good word for it. It really "gates" noise. It simply turns your signal off when you are not playing.

Noise gates are great for recording, and are great things, but they do not REMOVE buzz and hum. They just shut off the whole signal below a preset level.

Thanks for the response. You just demonstrated how BUZZ pickup will ocurr with a battery powered rig. I should have mentioned that too. Play through a little battery powered practice amp and see. Also, shielding is mostly ineffective. It may be somewhat effective in some cases, but never consistiently in all. Thanks for calling me the thinking mans chicken picker, but I have been an electrical design engineer for over 25 years. I've made a lot of mistakes, and hopefully learned from a few. But I know the buzz is still a challenge for us chicken pickers under most circumstances. :D :D

June 14th, 2005, 12:56 AM
Wow, it took a while to read thru all of the posts so far, but I think I am getting the picture.

Whereas I was thinking the problem was in the line voltage, or an interference with the AC voltage at the wall, the actual culprit is floating in the air around me at all times.


That does present a problem for someone dead-set in love with single coil pickups...

Makes a guy want to go out and design an anti-magnetic electro-magnetic proof bubble to practice in... (much like the bubbles one you might see in an old Avenger's episode when they would walk on water...)... crawl inside, plug-in and escape all electro-magnetic interference...

Not in 2005....

Not in 1955, either...

Well, I don't own a TV, but I do own a 17" CRT computer monitor, basically the same thing. But I am not all that close to the computer with my guitar or amp.... probably 12 feet away.

Also, I have a dual-XEON server running in this room... how would that measure up as far as stuff putting out funky interference? In more simpler terms, for those who don't know what I'm talking about... I built a computer with 2 CPUs instead of just one. Theorectically, the system will run faster and be more "powerful" with this advancement.

It also has a fan that spins 24-7

A pretty biog and rather loud fan, actually...

Possibly another culprit? The cooling fan on my server?

I'll have to do some experiemnts when I can shut her down and see how much she is affecting my guitar signal

The neighbor's TVs.... ha!!

I never would have thought about that one.

I am on the ground floor, kind of in a 5-stair-steps down lower-level apartment. Meaning you have to go 5 steps toward the earth to get into my apartment. If I look out my livingroom window, at about waiste high, is the front yard of the apartment complex. So, nobody is below me.

I'll have to see how the noise goes later at night when folks will be asleep, or early in the morning when they are gone to work...might just be the neighbor's TV, too...

and...damn, now you got me thinking...

across the hall in this building is the laundry room.

2 washers
2 dryers

not always being used, but big electric motors just the same


I am thinking the circuit I am plugged in to also has my refridgerator plugged in to it....

I can move my amp to a different location. I'm just not so sure how much moving the amp around is going to affect anything, if it's the pickups on the guitar that are causing the trouble...

But I could get farther away from the refridgerator. Where I am standing palying is only about 6-8 feet from the fridge and the fridge is always running, or running, then stopping, then running, as its on a cycle with the thermostat inside the fridge

how about that thermostst???

The thermostat for my apartment is on the wall behind the amp... would that casue any noise?

man... I'm already snooping around like "Sherlock Holmes"... looking for the ultimate culprit...

It is something in this apartment, I believe, because I have had these same guitars or one's like them all my life, but I've never had so much hum...

the server is new...................................

also have a DSL modem hooked up to the server, I dodn't know if that puts out any interference...

also, I have a Tripp-Lite 8-Port KVM switch attached to my computers so that I can use one monitor, one keyboard, one mouse, for multiple computers. I generally have more than one computer on...

maybe that's it...

do computers put out interference?

uh-oh, that's means I have to leave eBay long enough to practice my guitar???? aaaaaaaaaaaahhhhhh

I gotta have it
I gotta have it...


several thing to check... let me know if any of them are more suspect than others....

Jam Handy

June 14th, 2005, 01:24 AM
concerning the NS-2...

what that device is looking for is the swish of a flanger when you are not plucking the strings...

the "gate" works this way (in layman terms...)

--it will have a knob of some sort that you can adjust, if you turn it counter-clockwise it will have one effect, clockwise another effect...

(I don't know this effect "NS-2" in particular, just the priciple behind a noise gate)

if you have ever cranked you amp, and then hit the button on a flanger pedal, or some kins of an effect pedal that makes a modulating "swish" (chorus, or phase shifters do this too...) you will notice the white noise coming thru the cranked amplifier will be modified by the flanger, and you'll here it being modulated. Funny thing is, you aren't even playing a note...

The noise gate is designed to be able to sort-of turn the volume off for you if it doesn't sense that you are plucking the strings on the guitar

That way, that white noise "swish" is now inaudible

I would guess that one of the controls on the pedal would be called "sensitivity"...

If it is set up so the noise gate is "very sensitive" the slightest muting of the strings will cause the gate to kick in... sometimes that can actually be an undesireable thing, because just when you want to play with dynamics, and are trying to pick lighter, the noise gate turns the volume to zero, and you lose your signal

If the noise gate is set up to be "no so sensitive" the opposite will happen... even if you stop playing, it might take the gate a few milliseconds to turn the volume off...

so, somewhere in between "too much" and "not enough" is a good setting to be found on the noise gate...

If you're thinking its gonna work like a dbx noise reduction unit on a magnetic tape recording, it won't. That's not the principle behind the noise gate.

True dbx noise reduction has an encode stage while you are recording, then a decode stage while you are playing back. That's not the same as an amplitude change like you'd get with a noise gate.

The noise gate is working off of sound pressure (sort of) but more correctly, voltage... when the voltage from your guitar is high, and you are plucking away, the gate opens up, just like the gate was a faucet on your sink... then, when you tiurn the water off (stop plucking) the gate knows what to do, and slams the gate closed, preventing any signal to get to the amplifier... in affect, the noise gate is turning the volume on your amp to zero (sort of)

A dbx noise reduction unit is not working on amplitude, or volume... dbx is working on the frequencies being trasnferred from one source to the other... more like a glorified graphic EQ box.... (sort of)

There are frequenicies that can be recorded that aren't necessary for correct musical enjoyment. You've probably seen the spec for audio equipment measured in hertz, or cycles per second... basically, it has been known for years that a human being can hera, at best, from 20Hz to 20KHz...

A high-quality audio device will be able to reproduce those frequencies with very little loss at either end of the spctrum...

you've heard how a dog can hear frequencies we can't, right?

well, in the same similar way, a dbx noise reduction unit can shift out frequencies that we can't hear, especially higher frequencies that aren't need for the music recording, and actually block those frequencies from making it from the microphone to the piece of electro-magnetic tape.

this is noise reduction encoding

at playback, many of the cassette tape machines, and reel-to-reels back in the day would have the dbx decode feature built into them... I don't know all the technical stuff it is actually doing to the frequency spectrum, but without a dbx decoder, a dbx recorded source will sound rough and scratchy... it may even pop and click at times... that's because nothing is set up to decode the dbx signal for playback...

in the most very basic terms... a noise gate works like a volume control, whereas a dbx noise reduction unit works like a tone control...


so we cracked open the mysteries of magnetic filed interference AND dis-spelled the Noise Gate/Noise Reduction myth all in one thread...hot damn !!!!

what's next?... how about Total Harmonic Distortion (THD) that was always one of my favorite specs to watch for when buying an audio device of any kind... try finding a low THD (like 0.005%) rating on a wirless guitar transmitter and receiver system... I haven;t found one yet,,, typical wireless units are smacking our signals for 5% THD... OUCH!!!

If our Nakamichi tape decks did that, we'd throw them over a cliff!!!

Jam Handy

June 14th, 2005, 02:41 AM
Thanks, Terry & JH...
you guys explained the noise gate concept so well, that I actually understand it now!!

June 14th, 2005, 08:29 AM
I think that hum canceling pickups are the way to go. Bill Lawrence pups are reasonably priced, dead silent, and have a real single coil vibe.

Another related issue is RF noise. This is where you hear a radio station playing through your amp even when the volume is turned down. I used to live in a house that was horrible for this. There is a cheap remedy; radio shack sells magnets that clamp on the AC cord.

June 14th, 2005, 09:52 AM
I understand about hum-canceling pickups but I am trying to find a solution without changing the electrocins of my guitars.

Some of my instruments are very valuable, and it is my opinion that these instruments would lose value if even the screws were loosened on the pickgaurd, let alone firing up the soldering iron and removing or moving solder joints that have been ther in the same place for decades

should the instruments increase in value, part of that value will be "is the instrument original" ... swapping pickups is fun, but not an option for me here...

I believe that if I were to swap pickups in a guitar, it would have to be one that I didn't care whether or not the value of the guitar were to decrease. I believe the instruments I have were designed with specific PUPs to have specific tones, and I don't want to change that original design

It would be fun, however to buy, maybe a made-in-Mexico Fender Strat or Tele where I could experiment with all kinds of pickup harnesses. I would enjoy that, I really would.

I'm just not one to swap out PUPs in an Anerican made instrument that, too me is expensive, and to me has a great tone already

I believe I can find a solution by investigating the different electrical things going on around where I am playing the guitar...

Other than that... it seems like if I want to keep the guitars I play "as-is" I may have to live with some single coil noise... just like every player since the first No-casters and before.........


June 14th, 2005, 10:31 AM
I have outlined the main culprits of noise from the entire thread and re-written them all in this post. I also re-wrote what other possible "culprits" I have in my apartment that I have questions about. I thought it would be easier to continue if everything was in one place.

Ok, here goes:

You or someone else mentioned the following itmes might cause noise or create electro-magnetic interference in a single coil pickup guitar:


# Light Dimmers
# Fluorescent lights
# Neon Lights
# Transformers - all kinds - power transformers in amplifiers, walwarts and etc.
# Electric motors

# Television

#The neightbor's TV(s) (living in an apartment building)

# AC or DC power, it doesn't matter, the interference is in the sir around us

Now, Since I have now found out it isn't in the wiring of my apartment, but rather being produced by some device emmiting magnetic distrubances into the air, I have been investigating my apartment like "Sherlock Holmes" and I have come up with the following list of "suspects" who I might like to question concerning my single-coil noise (would any of the following have anything to do with the noise?):


(in the same room, but I don't know if they have an affect on the noise, I am asking you if they would are not...)

-CRT computer monitor in the same room?
-Dual-XEON based server in the same room?
-Cooling fans on the server? (one front one rear)
-Laundry room across the hall ? (big electric motors, 2 washsers, 2 dryers)
-Refridgerator in my apartment?
-Wall thermostat? (right behind amp...)
-DSL modem hooked to phone line and then to computer system?
-Tripp-Lite 8-port rack-mount KVM switch (switches between computers)?
-Having more than one computer on at a time in my apartment?
[I only use and have one monitor, though that's why I use the Tripp-Lite switch...]

That's all I could come up with at the moment....

Any tips on the one's I have listed as far as whether or not some of these things might be causing the magnetic interruptions?


Jam Handy

Tim Armstrong
June 14th, 2005, 10:38 AM
I find that wearing a helmet made from aluminum (or, if you're British, aluminium) foil keeps the buzzing in my head to a minimum (or, if you're British, a minimium).

Maybe that approach can help you!

Cheers, Tim

June 14th, 2005, 10:47 AM
Funny that I saw this thread. I bought a Highway 1 Tele last night (first single coil guitar that I own) and noticed an excessive amount of hum / noise as well. Andy Z recommended using a hum eliminator. I'm going to try and order one today. This might be what you're looking for:


Good luck!

June 14th, 2005, 12:49 PM
OK, maybe the engineer can tackle this...

By what the fellow (username: "tdowns") is saying up above is that there is a difference between the noise picked up by single coil pickups, and a 60 cycle ground loop hum.

The Ebtech Hum Eliminator is designed to eliminate groud loop hum, so they wouldn't help the noise a single coil pickup is making.

Yes, both can be heard through the amp, but, no... they are not from the same source...

60-Cycle hum, or what is known as "Ground Loop Hum" has got to do with a grounding situation between one or more electrical audio devices. The problem is in the power lines, or house wiring. The most common one I've seen here is when you're on stage, and the PA is coming unglued with ground loop hum. No guitars involved......

Single coil noise, as "tdowns" explained, is an electro-magnetic interference in the air, not in the power lines, the magnetic pickups of the electric guitar are actually picking up more than just the sound from the strings, they are picking up magnetic interference from other outside sources. Like a TV set. Take a Stratocatser over by the TV set and it will come unglued as far as how much noise it now starts to make. Almost as if there were some kind of little "noise gremlin" in the TV.

So, no... the Ebtech Noise Eliminator won't work, because the problem at hand isn't a 6-cycle hum or Ground Loop issue. Its just plain old single-coil engineering.

Originally, when I started the post, I thought it would be something easily solved by something like the Ebtech device, but I've learned here, that isn't the case.

Or... maybe I could track down one of those aluminimiuminum helmets Tim A. suggets...ha...

"We are DEVO -- D.E.V.O. ..."


June 14th, 2005, 01:05 PM

(in the same room, but I don't know if they have an affect on the noise, I am asking you if they would are not...)

-CRT computer monitor in the same room?
Absolutely. Same as a television.

-Dual-XEON based server in the same room?
-Cooling fans on the server? (one front one rear)
Yup. Cooling fans are noisy acoustically as well as electrically.

-DSL modem hooked to phone line and then to computer system?
Well, no electric motor there. You don't have a wireless setup do you? Or corless phones? I have intermittent problems that I suspect are caused by those. (Though it could be dirty power; haven't figured it out yet.)

-Tripp-Lite 8-port rack-mount KVM switch (switches between computers)?
Never noticed any added interference from one. It's a pretty simple switch, though. (Rack mount? Sweet.)

-Having more than one computer on at a time in my apartment?
More fans, more noise.

I used to have my amp/etc. setup in my office which is also the computer room. (At present there are 5 computers running in there right now, plus a KVM, plus a wireless router, etc.) The noise was incredible. In addition to the aforementioned case fans you get electrical noise from the hard drives spinning. (That's usually pretty faint, though, unless you're very close to the computer.)

I've since moved all my equipment to a spare bedroom. (More space gave me a good excuse to buy more guitars, too!)

I built a computer specifically for recording. It's a small form-factor case from Shuttle (www.shuttle.com, other manufacturers are making them now, too) and designed to be extremely quiet. I also have an LCD monitor instead of a CRT. This has cut done on the noise alot. I still get some 60-cycle hum (can't avoid it) but it's manageable.

If you're suspicious of any piece of equipment, just let your guitar sniff it out for you. Plug in, turn on your amp, mute the strings, and point the pickup at the suspect. You'll be able to tell if, where, and how much hum/noise it's giving off.

June 14th, 2005, 02:15 PM
The Ebtech Hum Eliminator is designed to eliminate groud loop hum, so they wouldn't help the noise a single coil pickup is making.

Hey Jam,

Thanks for clarifying that. I don't own an EBTech Eliminator yet so I wasn't sure. Can a noise gate help out at all, as long as it doesn't squash the sound?

With the EBTech, would you recommend the wallplug version or the 1/4" version? Where would the 1/4" version sit in the guitar chain?

(sorry for the temporary thread-jack)

June 14th, 2005, 03:45 PM
I think computer monitors are some of the worst offenders.

We used to practice in a commercial space with about 15 computers running. But the worst part was that we practiced right next to the electrical closet, which was unbelievably noisy.

Another thing to realize is that a high gain amp (mesa boogie) is has a poor signal to noise ratio. They really tend to amplify that 60 cycle hum.

In most cases, stage, studio, bedroom, the hum is just inherent to the electric guitar to me. I guess after a few years, I just started to ignore it, or flip the selector to a hum cancelling position. And after all, you don't hear it if you're playing, especially in a band.

June 14th, 2005, 04:35 PM
If you scroll up a few posts, I posted a rather bloggish-sized posy about noise gates compared to dbx noise reduction units.

(can a noise gate help...?)

In that thread I pointed out that a noise gate works like an automatic volume control. As soon as it thinks you aren't plucing the strings, it rutnrs the volume to zero. Then as soon as you start playing, it turns the volume back to line-level and away you go. Even when the noise gate is on, the 60-cycle style noise would still be there. Noise from a single coil pickup would still be there, too. The noise gate has only "turned the faucet off" so to speak, and then only temporarily. It hasn't, in effect, actually ELIMINTATED anything, just turned the volume to zero so you don't hear any amp hiss, etc. while you are in between songs, etc...

(Ebtech recommendation...)

About the Ebtech Hum Eliminator. I don't own one, but I understand the principle, and have read a lot of the product description ... First, you gotta be sure you have a 60-cycle hum problem.. This problem usually rears its head on a stage full of PA gear, where one of the power amps, or one of the signal processors (or something, sometimes hard to track it down) is either on a different circuit on the house wiring system, or is on the system but is "out-of-phase". The same situation can occur if you had an older signal processor in the rack that didn't have the third plug for ground, and it needed to be pulled out of the outlet, and turned upside down, and plugged in with the leads reversed as previous plugged, back into the outlet.... Once upon a time, even amplifiers didn't have that third prong for ground, and two guitar player might be on the same electrical circuit, and if one guy pulls his plug, and turned it upside down and re-plugged it into the wall, the hum would stop. That is "reverse polarity"... (well, kind of a hacked-up definition in layman's terms...)

I don't have an electrical engineering degree... I'm looking forward to (username) tdowns next post about all this... he DOES have an electrical engineering degree, and can tell you why (in all the terms scientists understand) all this stuff happens.

As far as a recommendation...hmmmm

Depends on your application.

Here's the link to all their Hum cancelling equipment:

Go over their products and then re-post later and we'll talk about it back and forth... heck, I'm learning new stuff, too... I know what their stuff does, put I don't own any...


June 14th, 2005, 04:58 PM
Unless you're recording a string quartet for audiophiles, you can't get too hung up with noise ..it happens in the world's top recording studios (with humbuckers even).

June 14th, 2005, 05:02 PM
One thing I just remembered about 60-cycle hum is that it can also come through the amp and the speakers when you have a bad cord.

(holy cow, this is gonna be a big list...)


-Guitar cord
-patch cord on your pedalboard
-cord you are using in the effects loop
-cord running between a your amp, and direct out, or the direct out to a PA input.

-microphone cable to mixer
-signal line cable from mixer to power amp
-bad speaker cord
-cords running to your rack signal proceesors from the mixer (and back)

and that's just the cords I can think of off the top of my head. If any of the inside parts of these cords comes apart due to wear, it can create 60-cycle hum in the system.

also, as far as 60-cycle hum...

a complete bar or club may just have wiring that is crappy... somewhere for that building, there has to be a rod driven into the ground, and then a thick hard wire copper wire has to be run from that ground rod, to the electrical box. If that grounding system gets compromised, the entire house could and might hum... and it won't be any of the above... (cords, etc...)

Now, this post is only to do with 60-cycle hum, not the noise a signle coil makes...

we have several issues all running together in this thread:

[very cool...]

1) The noise a single coil pickups makes and how to remedy it, and what causes it

2) The differentiation between magnetic interference of a single-coil pickup and the defining qualities of 60-cycle hum which is also known as "ground loop hum" (two totally different things...)

3) The operation of a Noise Gate and how it operates as an automatic volume control instead of actually doing anything to the noise of a pickup or the hum of a ground loop...

4) The comparison of a Noise Gate to a dbx Noise REDUCTION unit... with a layman's definition on how the Noise Gate works like an automatic volume control, and the Noise REDUCTION unit works like a glorified graphic equalizer filtering tones... a Noise Gate works on the volume of your stage signal... a dbx Noise Reduction encodes and decodes hiss and noise oput of a recorded signal by means of adjusting eqialization curves...

-- Note... DOLBY Noise Reduction doesn't operate on the same principle as dbx Noise Reduction. Basically, DOLBY just wacks the high-end and gives you back a hi-frequency cut, thereby cutting off all hissing frequencies... dbx actually encodes itself onto the magnetic tape, thereby requiring a DECODE device at playback... dbx cancels frequencies that produce hiss in recordings by transferring an encoded (sort-of anti-hiss) frequency set onto the tape... in comparison, Dolby Noise Reduction works in a manner much like taking the upper-frequency sliders on a very exansive, multi-channel graphic eq, and turning them to zero...


5) We had a brief discussion about wearing an aluminum helmet...hahahaha... hey, this might work...haha

6) We discussed an Ebtech Hum Eliminator, but then discovered there is a difference between the single-coil noise of a guitar and what is known as 60-cycle hum, and realised further that the Ebtech devices are meant to identify and correct 60-cycle hum problems, nit single-coil guitar noises

7) There was also a mention of a DC powered amp still having single-coil hum... so this definitively points out that the single coil noise is not connected to the AC power circuit. (very good point) (I have an old Pignose battery-powered amp... guess what... my Strat still hums when I get close to the TV, even if I'm plugged into my Pignose, battery powered amp...)


I had to take a nap because my head was full of thoughts about electronic disturbances...

I'm still in search of a way to extinguish single-coil hum for good... in any situation, bar, club, house, apartment, or environment...

Man... Leo left us too soon before he told us the end of that story... guess its up to us, now...

I know, I know... swap pickups....


June 14th, 2005, 05:04 PM
(but I love my vintage Alnicos....)

June 14th, 2005, 05:11 PM
I'm still in search of a way to extinguish single-coil hum for good...

JM, the undisputed king of blogging, I mean, posting in forums! Great stuff!

Here's a link I found on the Line 6 forums today:

What is the audibal difference between 60-cycle hum and single-coil hum?

June 14th, 2005, 05:59 PM
Nice link about shielding...

Once upon a time I shielded a friends Ibanez bass, and it worked pefectly... I also did the same on an Ibanez Artist 12-string one time... bot guitars had bad hum problems, and I cured the prob on both in this fashion... I went to some odd extremes, but here goes...

For you, I bought a ready-made product produced by Dimarzio called simply "Dimarzio Shielding Tape." Basically, it was a three-inch spool of copper foil with sticky-stuff on one side. It wasn't very expensive, either...

In fact, I just looked, and they still make it:


(or at least it looks like they still make it...)

The benefit of the Dimarzio product over the guy's aluminum foil/3M glue idea... is that the Dimarzio product already has the sticky stuf, and you don't have to chance getting goo on your best buddy...

First, I removed the strings and gained access to all the areas where electronic parts lived. Under the switch-plate, took the pickgaurd and pickups out... etc...

Then I simply took my time and did like a carpet-and-dry-wall job on every surface in the wood. (Consider the cavity has a floor, ceiling and walls...)

I did the floor of the cavity first, then I cut pieces for the walls of the cavity... then... I soldered the copper foil together on every joint that existed. I didn't leave any joint un-attended...

But I didn't stop there...

I cut very thin "straps" out of the copper and ran them from the "walls" of the cavity to the screw holes where the pickgaurd would screw in... I popped a hole in the little straps so the pickgaurd screw would pass thru when I was finished, then I soldered the little strap of copper foil to the foil on the interior wall of the cavity..

Then, I viewed the pickgaurd as being the "ceiling" and I covered the entire underside of the pickgaurd with the copper shileding foil.. If there were any seems, I soldered them together.

screwed it all back together, and no more hum...

I didn't have to connect the guitar's wiring harness to the shiedling job in any way... the little copper box I had just made, did all the work... like putting your pickups and tone pots into a little copper box...

(in the guy's link, he is calling for small-gauge wire, evidently with the intention to solder it to the shielding tape (foil) and then back onto the common ground of the guitar)... I didn't have to do that to get results... probably because when the pickgaurd was crewed on, it made a complete shielded box surrounding every electronic part, and in effect, this is what kept out the eletro-magnetic interference...

Fine for an Ibanez guitar, but I wouldn't want to put my Fenders and G&Ls through that kind of schtuff...


Tim Bowen
June 14th, 2005, 10:53 PM

Having tried a variety of noiseless guitar pickups and noise reduction devices over the years, I am a firm believer in BOSS noise suppression units. I started using the (now discontinued) BOSS NS-50 half rack unit with high gain amps, such as Mesa Boogie, in the late 1980's. After retiring the high gain amps, I settled into using low-medium gain "vintage-style" amps, and subsequently began to call on pedals for any additional gain that was required or desired. It was soon quite clear that the bulk of my noise floor was being created by gain-additive stompboxes. So I purchased a BOSS NS-2 pedal immediately after it was released. I now own several of those pedals, and have not worked a live electric guitar job since purchasing the first one, nor would I. I also regularly utilize the NS-2 for higher gain applications in the studio. No experience or opinion regarding computer-based home recording scenarios.

As Mr. Downs said, noise is again introduced after the noise reduction unit's threshold has done its thing. However, in my experience, 'the noise problem' is not so much a factor while "playing" - but can be quite the monkey wrench in the gears, in between phrases, upon starting tunes, and such.

The ISP Decimator regularly receives solid reviews. While I am curious about that unit, I've not pursued it, due to the fact that it does not contain a loop, whereas the NS-2 in fact does. My problems with noise suppression have basically occurred when I've tried to utilize it globally across the entirety of my signal chain. For instance, it has always adversely affected the response of time-based effects. I expect gain-based pedals to increase the noise floor, and I accept that. Therefore, I like the fact that the NS-2 contains a loop. I no longer utilize delays and modulation effects that audibly increase noise floor (which can substantially level the playing field, as some of the really good sounding units are quite noisy).

I've tossed out comments per the NS-2 on several threads here, including this one:


June 15th, 2005, 12:39 AM
Well, I understand what you are saying about the Boss unit, and I'm sure it works for what it does... but it is a noise gate, which is basically an automatic volume control...


The noise is always there, the pedal just turns off the volume to everything when you're not plucking your strings... And... when you are playing, even though your amp is louder than the noise, the noise is still there...

Sounds like a very decent pedal...

I'm looking for something else...

The Boss pedal, and any noise gate's solution is to cut the volume so you TEMPORARILY don't hear the noise... but...

The noise is still there, even when the volume is cut...

I am looking for a solution to the age-old problem of single-coil noise that solves the issue at all times, zero volume, and on ten...

I also want to find a solution without swapping pickups in my very expensive guitars (expensive to me, maybe not to other folks...)... I'm not a "pickup swapper" anyways... if I owned a lower-priced Mexican Fender, then I might swap pickups, but if I didn't like the guitars I am buying just as they are, I would not pay the money for them... there is absolutely no sense (in my opinion) of buying a guitar you don't like, only to bring it home, and un-solder all the factory connections, which may de-valuate the instrument (depending on the instrument of course)

About pickup swapping, and again, this is just my 2 cents worth... I have avoided that issue for many years because I give the guitars I buy (for the most part) a good test drive at the store before I buy them... that way, I'm happy BEFORE I buy the guitar, not after I put different pickups in it...

Don't get me wrong about aftermarket PUPs, though... its definitely fun to try out all kinds of different stuff... I do it myself...

Check out what a fellow said on eBay recently about his 1959 double-neck Gibson... he replied about folks wanting him to unscrew certain parts of the guitar and take photos of it to varify it was what he was claiming it was... he refused, because the second he unscrews one of the original screws that had never been unscrewed in all of this guitar's life, he devalued the guitar...

Ever collect comic books?

Mint means dead-mint, no wrinkles, and not even a corner folded over...

Read oit once, and its not mint anymore... mint, to a comic book means never read... a lot of people who read comics buy one to stash, and one to read... that's why...

kind of a blog about swapping PUPs, but "noiseless pickups" are a temptation only for someone willing to do the solder job on their axe...

so, there still is not a solution...

--its not the power at the wall
--it isn't solved if its gated (howbeit, that IS a temporary quick-fix...)
--can't use dbx noise reduction
--swapping pickups doesn't solve it (another quick-fix)
--a "hum eliminator" isn't the answer (that fixes ground loop hum, or 60-cycle hum)
--"Mur" commented about just living with it... but that doesn't solve it...


it seems that there is a glitch in the music industry awaiting an entrepeneur to step up and create a way to take a vintage instrument and get rid of its single-coil noise... WITHOU adding anything to the guitar, or causing it's market value to depreciate

we have temporary fixes, but no permanent fix...



Tim Bowen
June 15th, 2005, 12:53 AM
Jam, I understand. I think what we're talking about here is the equivalent of asking a washing machine to do the work of a dryer. If we're talking 'pure tone', I've not been made aware of a "fix", as yet. I am, however, quite happy with the practical *compromise* that has served me well.

On a side note, nobody hates pup swapping more than me! I do quite love Harmonic Design pickups, though.

Yes, I collected comic books! I'm partial to the old Marvel Comics 'Conan' series with the Barry Smith art, as well as old Warren Magazines pulp rags that contained art of Frank Frazetta, Esteban Maroto, Richard Corben, and other luminaries of the pulp field. I never put them in protective covers though, as I enjoyed looking at them quite often.

Stan Martin
June 15th, 2005, 09:56 AM
Your frustration is noted, but all of us on this board have tried various methods to quell or get rid of the noise.

Kinman, BL and Dimarzio make noiseless pickups, which are noiseless, but don't sound exactly like a single coil. Because they are not.

Shielding is somewhat effective, but it isn't a 100% solution either. I think the market you allude to is not profitable enough for someone. You cannot eliminate magnetic fields around us and therein lies the rub.

Life is about trade-offs and compromise. Guitars don't play perfectly in tune. So what. Buzz Feiten schmeiten. As soon as you lay your hands on the string you're going to pull it out of tune somewhat.

I miss beef that isnít tainted, tomatoes with flavor and women without tattoos.

June 15th, 2005, 11:02 AM
FWIW just try connecting or soldering a wire to the
back of the amp chassis and connecting it to a good
ground like a water supply pipe or ????. I've seen this
done in studios with quieting results. It's cheap and easy.

If your amps are fairly old try loosening the nuts
on the jack inputs enough to check/clean any corrosion
buildup from the nut underside and mating surface.

A friend bought some reasonably priced power strips
with built in hum or noise suppression. I don't know the
brand. Check places like Best Buy or Office Depot.
(If you knew this guy you would know the strips
didn't cost too much more above a std. one.)
He claimed to have good results with these. I don't
have one. Look for ones like for home theatre that
list "Filtering". These have built in chokes. I'm not sure
what type filtering, maybe RFI. You can look at ones
on Monster or the Alesis sight (expensive) write
down the suppression values and use that as a guide.

I have one Tele with BL noiseless pickups and fine
there, but if the noise is from elsewhere like amp
then no help.