Electro-Harmonix HumDebugger

You know why pickups hum, don’t you? Because they don’t know the words. (Cue the cymbal crash.) Funny? Maybe—but for more than half a century pickup hum has been the bete noire of every player who loves the vintage sound of a Strat, Tele, Les Paul Junior, Dano or other single-coil guitar. In technical terms, what occurs is that the pickup is, well, picking up the oscillation of the current coming out of the wall. This can range from 50Hz to 60Hz, but is generally known as 60-cycle hum. This hum is then made audible by the amplifier, and increased by any added gain stages—say, from amp volume, distortion devices, or compressors.

The term “humbucker” comes from that pickup’s ability to cancel hum by combining two single-coils with opposite polarities, wrapped in reverse directions, and wired together in series. Over the years, aftermarket pickup manufacturers have attempted to produce pickups that retain the vintage single-coil magic, yet cancel out this annoying noise. Players have employed, “stacks,” Lace Sensors, P-100s, and various flavors of “virtual vintage” pickups in an effort to cleanse their sound. While the quality of these solutions has vastly improved over the years, they all represent a compromise over the titillating tone of a true vintage single-coil in all of its noisy glory.

Enter the HumDebugger. This basic pedal—one on/off footswitch, and one mini-toggle for Normal or Strong effect—purports to be an answer to the single-coil lover’s prayer: a pedal that eliminates 60-cycle hum from your signal path, without having to sacrifice your ’57 Strat’s original pickups on the altar of signal-to-noise.

Is it the answer? Well, yes and no.

I tested the HumDebugger using a Fernandes Strat with Van Zandt pickups, a DiPinto Galaxie 4, and a new Danelectro Pro. I ran these into an Orange Tiny Terror head driving a 1x12 cab with an Eminence Texas Heat speaker, and a Reverend Hellhound combo. I added extra gain with a 65 Colour Boost and a Cusack Screamer Fuzz. I also checked it out using a friend’s vintage Gibson Melody Maker through an old Ampeg combo.

First, the good news: A single stomp on the pedal’s switch killed hum—simple as that. Neither my studio, nor my friend’s studio, is subject to excessive 60-cycle noise, so I never even needed the Strong setting. The HumDebugger did not diminish the noise caused by the Gibson’s proximity to my friend’s CRT computer screen, but, in front of my own LCD screen—plugged into Guitar Rig, through an M-Audio 1814 firewire drive—the signal from my Van Zandts was as quiet as a computer mouse. Through an amp once again, I dimed the boost on the 65 pedal through the overdriven Tiny Terror—no hum. I plugged in the DiPinto, with its normally noisy pickups—hum gone. The Dano lipsticks are surprisingly quiet to start with, but add the HumDebugger and zero hum. At a low volume, with a clean setting on the amp, and no distortion pedal, there is barely any audible tonal change. If you listen closely, you might hear a diminishing of the low end that varies from guitar to guitar, depending on the inherent bass frequencies of the instrument. My DiPinto is tuned like a baritone, so it was more noticeable there, but the Strat, Dano, and Melody Maker—not so much.

However, the HumDebugger is far from a Holy Grail. At higher volumes—and, especially, at higher gain levels—the low end roll-off becomes quite noticeable. In addition, the sound develops a slight hollowness—very much like the sound of a distant room mic or a short delay. This tone is not necessarily unpleasant—it’s just different from the un-Debugged tone. In some really noisy rooms, you may be forced to use the Strong setting, in which case you may experience one or two notes dropping off in volume.

So, do you need a HumDebugger?

If you play traditional jazz, and love that P-90 equipped ES-175, the HumDebugger could save your life when you’re stuck in front of a neon sign in the corner of the bar—and it will save you with a minimal sacrifice of tone. My friend, who plays jazz, said, “Finally, I can take my Melody Maker out and play it live.”

If you rock and roll, you can turn it on for those clean intros, and off during high-gain solos. In the rare case where the hum is so bad you need to have the HumDebugger on for the whole night, you might find that you can live with the sonic changes. Some nights, you may not need to turn it on at all.

In any case, this pedal allows you to stick with the authentic single-coils that you love, and only compromise your low-end spectrum when you have to. The Electro-Harmonix HumDebugger may not be the ultimate solution to hum, but it should absolutely keep you from considering other alternatives—such as switching pickups or guitars.