Sudden extra hum in a single coil pickup. *update*

[Dan Beller-McKenna]

I have almost exclusively single-coil pickups in my three steels (except for a humbucker on the C6 neck of my Carter) and two teles. I get the usual single coil hum, and I'm okay with it. Last night I arrived at a gig with my Carter D-10, got set up, fired up my amp, and: woah! Unacceptable hum. Like the usual 60 cycle hum but on steroids. We were outside and the stage lights were not plugged in yet, and no other amps were getting this hum, so I doubted it was an issue with the power supply or some wiring around me. With a little checking I was able to determine that it was the pickup on the E9 neck of my Carter (got the hum plugging directly from the steel to the amp, but only with E9; guitarist's single coil tele got no extra hum going directly into my amp). Confirmed when I checked it at home this morning into a different amp.

I had just been playing the Carter (into the same amp I brought to the gig) that morning with no hum. I poked around underneath this morning when I got home (same hum; A/B'd against my Super Pro which had no unusual hum; it's the Carter E9 pickup), and there does not seem to be anything amiss with the wiring.

So: can a pickup suddenly go "bad." It still has full signal, just accompanied by an unacceptable hum. It's a relatively new (one year old) pickup from a reputable steel pickup maker. Has never had a problem before.

Thoughts?

[Dan Beller-McKenna]

I should add that the gig was not a bust. I keep an Electro Harmonix Hum Debugger in the emergency bag in my car just for such situations. I only need it every couple of years or so when I encounter a problem room, but when called upon, it never fails me. Worth its weight in gold!

[Ricky Davis]

Just sounds like to me; the E9 neck lost or doesn't have the ground wire; grounded/touching any part of the changer, where the strings are. You either have to have a splice in ground wire from pickup to run under bracket or anything touching any part of the changer mech; before going to input jack; or extra ground wire running from input ground/jack to a spot on that changer mech(under a screw or raise spring bracket...etc.
Ricky

[Dave Grafe]

That happens to me if I put my fan or other electrics in the wrong place relative to the pickups. That can make the sound guys crazy as it comes and goes with the volume pedal. True big deep 60 cycle, none of this wimpy 120Hz noise anybody can make

Pickups can and do go bad, sometimes making a lot of noise and very little or none at all of what you intended. If your steel is still at the usual normal volume when this noise appears it's unlikely to be the pickup itself. If so check the wiring of the guitar, particularly on the ground side, check your cables and amp connections.

Lastly, if everything else checks out okay, verify that the VP is not plugged in backwards. It is essential to always do this step last, as it's the easiest to fix

[Donny Hinson]

Did you check the cables?

Also, try loosening the jack on the guitar, rotating it slightly, and then re-tightening it.

[ajm]

Do you have an ohm meter/DVM/DMM/whatever?

If so............
Plug a cable into the guitar.
Measure the ohms between the tip and sleeve.

What do you get?

[Dan Beller-McKenna]

Thanks for all the replies.

As I explained in the original post, I have ruled out all other parts of the signal chain: it is the E9 pickup. My assumption is what Ricky suggested, some ground wire has become loose. . I Installed the pickup, a Steeltronics, following the manufacturers instructions. But I quite frankly stink at soldering, and all things wiring, so it is possible I did it poorly, but just well enough that it would work for a year or more before some slight bump (not that I'm aware of any occurring between Thursday morning when it was fine, and the Thursday evening when it was not) nudges something out of place. I can't find anything amiss with the wiring to the terminals underneath, and the jack is the original carter wiring (and for good measure I took off to check the wiring there too. All solid). I am guessing something about the way I installed the pickup in the cavity is causing the problem.

My multimeter died a while back. I went out and bought a new one this morning. Taking a reading as ajm suggested shows 0 resistance (far right) at every setting (RX1, RX10, RX100) on the meter as shown here:




Next steps?

[Donny Hinson]

No resistance? That means the pickup is open, and producing a signal through capacitative coupling in the windings. Normally, that produces a lowered volume with a thin sound (no bass). Why it’s producing a “normal” sound and tone, except for the hum, is beyond my experience. Anywho, now you know what’s wrong.

[Dan Beller-McKenna]

My bad: that multimeter didn't measure ohms high enough (I tried it on a bunch of perfectly good pickups and they all gave the same reading). I returned the meter and got the right kind and the humming pickup measures perfectly normal (17.5). I will pull the pickup out of the cavity and see if there is anything amiss in there. If not, I might pull the pickup entirely and put a Truetone I have in there and see if things improve.

[Scott Swartz]

Dan, if interested you can give a call at 314- two six 7 - 4 six two one and I can help you trobleshoot it via phone or facetime.

[Dan Beller-McKenna]

Thanks, Scott. I'll take you up on that. Gonna be a few days before I can get to it; I'll contact you to figure out a time.

[Dan Beller-McKenna]

Many thanks to Scott Swartz for a couple of in-depth, detailed phone consults, and to Bruce Derr for his masterful rewiring to replace my rats-nest soldering.

Major upshot: it is not the Steeltronics pickup (nor is it something in the wiring).

After consulting with Scott, I redid the wiring myself as neatly as I could. Playing the Carter at home it seemed to have more hum than my other two steels with single coils, but not so much that I couldn't play it. However, when I took it out on the bandstand last weekend, it felt like too much hum (different stage, amp, and ensemble form the gig that prompted the original post). Not unplayable hum, but enough that I avoided sustained notes (especially harmonics) where I would have to open up the volume pedal all the way. That sort of thing is not an issue on my other two steels with single-coils.

So I swapped out the Steeltronics for a Truetone. No difference. At this point I was sure it was just my poor soldering technique, so I had my buddy Bruce Derr come by and do it right. After he meticulously redid the wiring, soldered it up impeccably, and checked out all of the grounding on the instrument, the same old hum was there.

After another consult with Scott, and after perusing old threads on the Forum (like this one), and looking at dozens of pictures on Carters online, my take way is that Carters just don't take single coils particularly well. (Scott had some off the top of the head theories of why this might be.) So I'm off to humbucker land (and, to be fair, this axe had a humbucker in it when I acquired it).

[Richard Sinkler]

I don't think it is a "Carter" issue. The brand of guitar should make little or no difference as long as the wiring is good. I have a BL XR-16 on the E9 neck of my Carter with a switch wired in to switch it from Humbucker to single coil. I use it in single coil the most, I have very little hum. And, the Tele plyers and others with single coils also have some hum, sometimes worse than mine. Mine only gets bad in cetain venues, but the other single coil instruments hum too.

[Dan Beller-McKenna]

Point well taken, Richard: let's just say this Carter doesn't take single coils well. I will say though, that the pictorial record (i.e., a Google images search) suggests that not many people have straight up single coils in their Carters. I suppose some may have a single coil tap switch on their humbuckers as you do. For that matter, that's what Bruce Derr has in his Carter.

[Dan Beller-McKenna]

I finally bit the bullet and put a humbucker in there. Bruce Derr was kind enough to gift me a GL 10-1 he had languishing in his pickup drawer. Somewhat to my surprise, I like it. I had an inkling I might after watching a video of Micky Adams cycling through a series of pickups in his MSA, where the 10-1 sounded quite good.

I acquired this Carter with an E-66 on the E9th neck, which was fine, but I felt the need to switch to a single coil. I think the 10-1 gets me closer to that sound than the E-66, and importantly, there is no more hum(!)

[ajm]

I have had personal experience with both the E66 and the 10-1 in a single neck Carter.
The E66 definitely sounds brighter.
FWIW, I stuck with the 10-1.

However, if anyone actually knows..........

Is the E66 a single coil or is it a humbucker?

And.....

Is the 10-1 a single coil or is it a humbucker?

I looked on the George L web site first and couldn't find anything.
I believe that they are both humbucking.

[Dan Beller-McKenna]

Pretty sure they are both humbuckers. In fact, I just assumed all GLs were humbuckers, but I don;t actually know that for a fact.

[Jon Light]

I got my Carter around 1999 or so with a GeoL TPPP (Traditional Pole Piece.....) It was an odd duck and for love or money I could never get anybody to say whether it was sc or hb but it sure looked like a sc. Of the pickup sound samples that Carter produced, it was my favorite. But it was microphonic as hell and apparently I was not the only one with this problem. I tried a BL 912 for a short spell but it was a poor match with the guitar. BL XR-16 was the winner. I can't recall if I tried an E66 in the Carter or if it was the Fessenden, specifically for one neon-sign-awful Brooklyn barroom but while it did the humbucking job, I did NOT like the pup.