Dealing with 60-cycle hum from clients' guitars (possibly?)

[jgimbel]

I've done a lot of searching on the topic but not really found exactly what I'm looking for. Long story short, it seems that guitars down here in my basement space have much more hum issues than when they're elsewhere. It's a bit of a confusing issue. Here's the situation:

Amps are dead quiet down here on standby, this isn't a hum that's constantly there no matter what. The hum comes with single coil guitars. It does change as you change your position relative to the amp. At best it's really not bad, but at worst it's pretty bad. I've done my best to locate the source, and everything just points to the guitars. There are fluorescent lights down here, but the hum doesn't change when using the incandescents or without the lights on. The problem also doesn't change the amp is plugged into a different outlet on a different circuit, and it also doesn't change when plugging into my Furman. And since the hum isn't there with humbuckers, that says to me that issue is the guitars. My main guitars are pretty cheap and it's not crazy to think that the grounding isn't perfect on them. However when I've brought those guitars other places, they're practically silent. It's like the problem down here is that something is amplifying the issue that isn't ideal in the guitars in the first place. I deal with it fine when recording myself, just watch how I'm positioned and find the best spot. The place it becomes an issue is when clients come here and say "wow my guitar/amp don't hum like that at home!". And though with some careful positioning the situation is fine, it still doesn't instill a lot of confidence to the client.

This is an older house, so it wouldn't surprise me if something with the wiring has to do with that, however the problem is only there with single coils, no issues with humbuckers, so it doesn't seem like a constant issue caused by the house. Also I don't really think I'm going to be able to do anything with the wiring in the house. I don't own it and I really don't have the budget to be digging out walls and things like that.

Is there anything at all that might be able to help this? The power conditioner I have, like I said, doesn't change it. I'm looking at things like the Ebtech Hum X, but seeing as the problem isn't just a constant hum from the house, I'm kind of doubting that would have much effect if any. I've hated the sound of noise gate pedals like the Boss, it's just so obvious when the hum comes back in while playing, and it sounds much better to me to just have some hum in there and the listener kind of just tones it out. Many of my clients are people with no recording experience/barely any money, so trying to get people to do stuff with grounding their guitars before they come in just will not work. Once in a while I have a client that is willing to do what it takes to get the best recording, but most people I work with want to get in, get out, and be thinking about it as little as possible. Do I have any options at all? I don't have a huge budget but if I can spend $100 and relieve this that'd definitely be worth it for me.

[Dominick Costanzo]

Your problem is electromagnetic interference (EMI)
Somewhere near you, not necessarily in your house, something is radiating an electrical field. This is what the single coil pickups are picking up.
Possible sources in your home would be CRT monitors or anything with a motor or transformer - ie just about anything electrical.

Build a knock-down-able 7' x 4' x 4' frame of 2x4's or 2x3's with one side as a hinged door.
face every side, including top & bottom, with copper screening.
Overlap screen on each surface so all the screening touches all the other screening.
Attach a 14 gauge wire to the screen and attach the wire to system ground.
You now have a grounded Faraday cage.
Find the location in the room where hum pickup is least.
Place the cage there.
Put the guitar player in the cage.
Orient the player to face towards (Jim Williams's words} "Mecca" for minimum hum.

You'll need
12 12' 2x4's or 2x3's
2 door hinges
38' of 4' wide copper screening
screws, nails and a staplegun

[vvv]

One thing you might try is to see if that interference source is actually in yer house.

Using basic trouble-shooting protocol:

Turn on a amp with a obviously offending guitar.

Can you (at the breaker box) cut the power to the whole house except yer recording room? And then bring the rooms on line, one at a time?

In the alternative, unplug everything and start plugging it back in. (I reco plugging and unplugging because some stuff, ex., TV's, is only on stand-by when you switch it off.)

If you can ID the culprit(s), you may be able to move it/them or put a switch on 'em (ex., use a switched power-strip.)

Good luck.

[Nick Sevilla]

Hi,

As Dominick pointed out, it is EMI.
This is interference that travels through the AIR. Not through the power wires.
You do need to find the cause of the EMI, and turn that off if possible.
ANY refrigerator, CRT TV (not LCD) or other older electrical appliance may be causing this EMI.

Trust me, I own 3 Stratocasters, and the one which has active electronics is the only one that does not suffer from EMI. The other two can do so, but I play them where I do not get EMI, in my studio. Anywhere else in the San Fernando Valley (LA), is pretty much full of EMI.

If you cannot get rid of the EMI, then you can always IGNORE it. Lots of classic records have EMI all over them, and it did not stop them from being made nor selling at the store.

Cheers

[Gregg Juke]

The cage sounds like a great idea, and we know you're a "building guy," jg!

Single-coils are notorious for this type of problem. The standard fix is lifting the ground, if the amp has a switch for that. You could try a direct box, and use the XLR signal to re-amp later, and use the amp just for the room/monitoring. You could plug the amp into the HUM-X (but you'll still have single-coil pick-ups). You could position the player so that the hum is minimized. You could record just the hum, and try to cancel it out with inversion in post. But none of these is ideal for you probably, so try the cage thing...

GJ

[jgimbel]

Thanks for the help guys! Unfortunately (or fortunately I suppose) the problem isn't quite bad enough that it warrants me having a big enough budget to build a cage like that. Also like I said a lot of folks coming through here are on the beginner side. Some clients I have are willing to do what it takes to improve a recording, but the idea of even suggesting to people that them playing in cage would help would probably cut the little business I'm doing in half. But the hum definitely isn't bad enough that it's an issue when it's in there. Initially when recording myself, at the end of a guitar track I'd try to fade the guitar out as the chord fades and try to make it like there is no noticeable hum, but I've found I much prefer it to just be there. Recordings here are not really super perfected anyway, not lofi by any means but a perfectly quiet strat is not something to be expected here.

I don't think I'll be able to make DI/reamping a standard practice here as a lot of people are only here for one day so I don't have their amps here anymore, when they're not using one of mine.

I do have a TV down here, though it's never on during recording! It's not an LCD, any chance this would still cause hum even when off? I'll try unplugging it. I'll also definitely try the circuit box. Unfortunately ours in this house is pretty poorly labeled (I need to address that!) and the wiring in the house is a little strange, to me anyway, like I believe the corner of the house that my computer in is on the same circuit as the room directly above it, but not the outlet next to it. But I'll definitely try and see if I can track down the culprit. Not a problem to ignore it though. The people who mind it enough to not want it in their track are generally okay with finding a position to stay in.

Thanks so much for the help! If it ever becomes more of an issue and I have the budget for a Faraday cage you know I'll do one of my long-winded "this is how I did this" posts!

[ubertar]

Invest in a guitar with single coil "noiseless" pickups. Then, when someone gets too much hum, they can use your guitar and get a sound that's fairly close to their usual sound but without the hum. A lot cheaper and easier than building a cage.

[???????]

Faraday cage won't necessarily help with all types of EMI, unless said faraday cage was made of mu metal.

It might help. It might also be a huge waste of time, depending on what type of interference you're dealing with. If you're dealing with magnetic fields at 50/60 Hz (i.e., from a transformer nearby), the faraday cage won't help much, if at all.

[jgimbel]

Invest in a guitar with single coil "noiseless" pickups. Then, when someone gets too much hum, they can use your guitar and get a sound that's fairly close to their usual sound but without the hum. A lot cheaper and easier than building a cage.

I was thinking of doing this. I've been playing guitar for over a decade and I've been feeling like it might finally be time for me to upgrade to a guitar that isn't just "really not bad for how cheap it is" and I've been planning on just getting an American Standard Strat. The Deluxes do have noiseless pickups, though it'd be a bit of a stretch for me to get one. The only reason the Standard would be doable is because I have a friend whose father owns a somewhat large national music store chain (not Guitar Center and not owned by them!) and my friend said she could get me a discount on the guitar, so I'd get a $1000 guitar for at least a small chunk less than that. Maybe I'll get the standard and then when I can afford it, get a set of noiseless pickups.

My bass actually has noiseless pickups, and it's still got some of the same hum. It's not as dramatic or distracting as with the strat or my tele, but it's there.

[Gregg Juke]

Spoken like "Doc" from West-Side Story:

"Would putting in a set of hum-buckers be such a sin?"

GJ

[???????]

I've never met a noiseless single coil I like.

Have you heard of the Suhr Backplate Silent Single Coil system?

That looks promising, though I've never tried one.

[jgimbel]

Spoken like "Doc" from West-Side Story:

"Would putting in a set of hum-buckers be such a sin?"

GJ

Nope, though generally I like single coils for most of what I do, and a lot of what people coming here do. I do love humbuckers for certain things!

[top_ape]

I'm surprised no one has suggested investing in some audio restoration/repair plugins. Yes, the ideal is to capture the source as close to how you'd like it to sound to begin with, but for a couple hundred bucks (in addition to what you're already doing to minimize hum pickup now) you could remove the hum and other noise from your tracks, and also from tracks your clients might bring to you. Hum removal can be done pretty transparently.

Side note: I'm curious how effective it might be to instead of building a full-on "cage" - maybe just a baffle or 2? Might that be enough to shield one from the offending source of EMI?

Could one conceivably construct a regular baffle with the addition of a layer of copper as described, which would then serve 2 purposes? I'm curious.

[???????]

I'm surprised no one has suggested investing in some audio restoration/repair plugins. Yes, the ideal is to capture the source as close to how you'd like it to sound to begin with, but for a couple hundred bucks (in addition to what you're already doing to minimize hum pickup now) you could remove the hum and other noise from your tracks, and also from tracks your clients might bring to you. Hum removal can be done pretty transparently.

Side note: I'm curious how effective it might be to instead of building a full-on "cage" - maybe just a baffle or 2? Might that be enough to shield one from the offending source of EMI?

Could one conceivably construct a regular baffle with the addition of a layer of copper as described, which would then serve 2 purposes? I'm curious.

Unfortunately, to work properly, a Faraday cage requires complete coverage. For another thing, low-frequency magnetic fields are not significantly reduced by faraday screening. This is one of the biggest sources of hum in single-coil guitars, which is why you don't usually see them used in this fashion.

to significantly attenuate magnetic interference would require a magnetic metal such as iron, nickel, or mu metal-- which would make for a very expensive cage.

I tried experimenting with this once by building an aluminum cage completely around the power transformer of a guitar amp I was building. It did absolutely nothing to reduce hum pickup when a guitar pickup was placed near it.

[Dominick Costanzo]

A quick way to see if the cage will be effective in your space -
Wrap a 4' square piece of copper screening around the offending guitar
Screen should not touch any metal part of the guitar.
Ground the screen.