The Whoosh That Launched a Thousand Air-Guitarists: MXR M117R Flanger

Before Eddie Van Halen taped it to a piece of plywood with black duct tape somewhere around 1978, the flanger was a studio curiosity — an effect that required two tape machines running in tandem and a producer’s willingness to spend half a session chasing a sound. The MXR M-117 Flanger changed that equation overnight. It put the jet-plane sweep, the queasy time-warp shimmer, and the hypnotic metallic throb into a gray box you could put on the floor and step on. Forty-plus years later, Dunlop’s reissue — the M117R — carries that same bucket-brigade circuit, those same four knobs, and the same capacity to make a guitar sound like it’s simultaneously in the room with you and hurtling through the upper atmosphere at Mach 2. That combination of simplicity and sonic wildness is exactly why the MXR Flanger has never gone out of production, and why it still shows up on serious pedalboards in 2026.

A Brief History of the Swoosh

Flanging as an effect predates guitar pedals by decades. The term itself comes from tape-era studios where engineers would press a finger against the flange of one tape reel to slightly slow it down relative to a duplicate reel playing the same content — the interaction of the two slightly detuned signals produces a comb-filtering effect that sounds like the world is rotating. Les Paul experimented with it. The Beatles’ “Tomorrow Never Knows” used tape flanging. Studios charged accordingly.

MXR changed the access model. Founded in Rochester, New York in 1972, the company built its reputation on dense, no-nonsense stompboxes: the Phase 90, the Dyna Comp, the Distortion+. When their engineers applied bucket-brigade device (BBD) technology to flanging in the mid-1970s, the result was the original M-117 Flanger — a pedal that replicated the tape-flanging effect in real time, triggered by foot, for a fraction of the studio cost. The BBD chip at its heart stores audio samples in capacitors and delays their playback, creating the same short, sweeping delay differential that the tape machines produced. Unlike tape, though, a BBD chip can be swept across its delay range continuously and automatically, controlled by an LFO — which is exactly what the Speed and Width knobs on the M-117 let you do.

The original ran on 18 volts — higher rail voltage than most of its MXR siblings — because the extra headroom allowed the BBD circuit more dynamic range and a lower noise floor. That 18V spec has carried forward unchanged to the M117R reissue, which is one of the reasons Dunlop markets this pedal as a faithful recreation of the original rather than a modernized approximation. The circuit architecture is the same. The character is the same. The controls are the same four knobs, in the same configuration, doing the same things they did when Eddie Van Halen was discovering what happened when you dimed the Regen and chugged an open D chord through a Marshall stack.

Who Actually Played It: Verified Artists

Eddie Van Halen — The Defining User

No conversation about the MXR Flanger happens without Eddie Van Halen, and for good reason. In a 1980 Guitar Player interview with Jas Obrecht, Eddie described his makeshift pedalboard with characteristic directness: “It’s a piece of plywood with two controls for my Echoplex on it, an MXR Phase 90 that I’ve had for years, and an MXR flanger. They’re all taped to a piece of board with black duct tape.” This wasn’t a sponsored arrangement or a record-label endorsement — it was a young guitarist from Pasadena using the tools that sounded right to him. The fact that those tools happened to be MXR’s most interesting designs is a testament to the company’s engineering instincts as much as to Eddie’s ears.

The sounds Van Halen produced with the original M-117 defined what rock flanging meant for the next generation of players. “And the Cradle Will Rock…” from Women and Children First (1980) opens with one of the most recognizable flanged riff introductions in rock history — that churning, metallic sweep over a brutally heavy power chord progression. “Unchained” from the same album features a different application: a tighter, more rhythmically integrated flange effect that seems to breathe with the riff rather than coat it. In a Guitar World interview from 2014, Eddie explained his settings with the kind of precision only someone who’s been playing the same gear for thirty-plus years can provide: “I set the three knobs on the left between 11 o’clock or 11:30, and the last knob on the right is all the way up.”

The M117R is the reissue of exactly that pedal. When Dunlop later worked with Eddie to create the EVH series of signature gear, they developed a separate model — the EVH117 — that added a custom switch dialing instantly to the “Unchained” setting. That pedal is a tribute product. The M117R is the original instrument, in faithful production form, with the same four knobs that Eddie adjusted in dressing rooms and rehearsal spaces across three decades. Eddie Van Halen died on October 6, 2020, but his relationship with this circuit is documented in his own words across multiple decades of interviews. This is as confirmed as guitar history gets.

Kerry King — The Thrash Metal Angle

The MXR Flanger’s reach extended beyond the hard rock world into the emerging heavy metal underground. Kerry King of Slayer has been documented using an MXR Flanger on his pedalboard since the band’s early 1980s days, and the pedal has appeared in subsequent Premier Guitar Rig Rundown coverage of his setup. King’s application is characteristically extreme — where Van Halen used the flanger with musical restraint and dynamic awareness, King deploys it as a textural aggression device, adding a metallic, destabilizing quality to Slayer’s already chaotic sonic landscape. The MXR Flanger on a drop-tuned seven-string through a high-gain amp stack is a different instrument than the same pedal into a modded Marshall in a Pasadena rehearsal room, and Kerry King proved it. The pedal’s ability to function in extreme gain contexts — maintaining its sweep character without dissolving into mud — is one of its genuine engineering achievements.

No Confirmed M117R Connection: Stone Gossard

Various web sources attribute the M117R to Stone Gossard of Pearl Jam, but the documented evidence points to the Ibanez FL-305 Flange with Delay as Gossard’s flanger of choice during the Riot Act era, which is where most of his detailed rig documentation originates. No Premier Guitar Rig Rundown or primary-source interview confirms Gossard on the M117R specifically. He’s a legitimate guitar hero with a documented love of interesting pedals — the attribution has surface plausibility — but surface plausibility isn’t the same as primary-source confirmation. Gossard gets a mention here as a player whose Riot Act-era sonic experiments (particularly the flange-heavy rhythms of that period’s material) represent the kind of musical territory the M117R naturally inhabits, even if his personal flanger of record was a different box.

Specs and Signal Chain Position

Understanding the Four Knobs

Manual is the frequency center control. It determines where along the frequency spectrum the flange effect is anchored when auto-sweep is disengaged. Think of it as selecting which part of the sonic range the comb filtering targets — lower settings emphasize the low-mid frequency sweep; higher settings push it toward the upper harmonics. When auto-sweep is active (Width above zero), Manual serves as the sweep’s center reference point.

Width is the most important operational control on the pedal. Rotate it counterclockwise to zero and the auto-sweep LFO disengages completely — the pedal stops moving on its own and sits at a fixed flange position set by the Manual knob. This is a genuinely useful mode that most players miss: static flange creates a chorus-adjacent thickening effect without the motion, essentially adding a fixed comb-filtering presence to your signal without any audible pulsing. Rotate Width clockwise and you’re introducing automatic sweep, with wider rotation producing a more dramatic sweep range from the effect’s low point to its high point on each LFO cycle.

Speed controls the LFO rate — how fast the sweep cycles from its low extreme to its high extreme and back. At minimum settings, one complete sweep might take ten or fifteen seconds, producing a glacially slow, almost imperceptible movement that works as an always-on subtle thickener. At maximum, you’re in jet-airplane-takeoff territory, with the sweep cycling multiple times per second and producing the rapid, destabilizing wobbly sound that defined early 1980s heavy rock.

Regen (short for regeneration) feeds the wet signal back into the flanger’s input, intensifying the comb-filtering effect and pushing the sound toward more pronounced metallic resonance. Low Regen settings are polite and musical, adding depth without obvious artificiality. High Regen settings are aggressive and distinctive — this is where you dial in that deep, almost machine-like flange character that sounds like the signal is being folded back on itself. Eddie Van Halen’s documented setting has Regen “all the way up,” which explains why his flange sounds as pronounced and self-confident as it does — there’s nothing subtle happening in that circuit when you’re maxing the feedback.

The 18V Power Requirement

The M117R’s 18V power requirement deserves attention before you plug it into a standard 9V daisy chain and wonder why it won’t power on. Two 9V batteries work (the pedal accepts them in series), but for pedalboard use you need an 18V output — the DC Brick, Iso-Brick, and Mini Iso-Brick all have 18V outputs, but not every compact power supply does. The Strymon Zuma, Voodoo Lab Pedal Power 2+, and TrueTone 1 SPOT Pro all offer 18V capability, but budget supplies and basic daisy chains will leave the M117R dead on the board. Check your supply spec before purchase. The 39mA current draw is modest for 18V — any 18V output rated 50mA or higher handles it comfortably.

Signal Chain Placement

Flangers are modulation effects, which means they belong in the modulation slot of a traditional signal chain: after drive pedals, before delay and reverb. The logic is that you want the flanger sweeping a signal that’s already been shaped by gain and EQ, not sweeping raw dynamics that will then get further compressed and filtered by downstream effects. Running drive into flange into delay gives each effect a defined role and a clean input to work with.

The M117R is also worth considering in an effects loop. Many high-gain amplifiers have parallel or series effects loops designed specifically for modulation and time-based effects — routing the M117R through a loop means the amp’s preamp handles gain shaping while the flanger processes the post-preamp signal. The result is often more controlled and musically coherent than running a flanger in front of a high-gain amp stage, where the sweep can interact unpredictably with the preamp’s compression behavior. Kerry King’s use of flanging in extreme-gain contexts speaks to how well the effect can work when the signal chain is organized correctly.

Tone Recipes and Settings

How the M117R Fits in the MXR Modulation Family

MXR’s current modulation lineup gives players several choices, and understanding where the M117R sits requires knowing what its siblings do differently. The M152 Micro Flanger is the compact alternative: smaller footprint, simpler control set (three knobs instead of four, no Manual), lower price ($125.99 MSRP). The Micro Flanger is appropriate for players who want flange on the board without dedicating significant space or money to it. The M117R wins when you want manual frequency control and the sonic depth that comes from the full circuit implementation — it’s louder, more detailed, and more configurable. The Micro Flanger is a convenience product; the M117R is the serious tool.

The MXR M234 Analog Chorus occupies adjacent sonic territory. Both use analog BBD circuitry to create time-based modulation, but the fundamental character differs: the Analog Chorus produces a smooth, pitch-modulated doubling effect through a fixed short delay that cycles in pitch. The M117R produces a comb-filtering sweep that dramatically reshapes the frequency content of the signal. Chorus tends to sound “wide”; flanging tends to sound “metallic” and “swept.” The M117R can approximate chorus behavior at gentle Width settings with Regen low, but it won’t fool anyone who knows both effects — the character is fundamentally different. Some players use both on the same board, with the Analog Chorus for clean-channel shimmer and the M117R for high-gain modulation duties.

Comparing the M117R to competing flangers: the Electro-Harmonix Electric Mistress is the other legendary analog flanger, preferred by David Gilmour (Pink Floyd) and Robert Smith (The Cure). The Electric Mistress has a looser, more psychedelic quality — its sweep feels less precise than the M117R’s, more impressionistic. The M117R’s four-knob design gives you more surgical control over where the sweep lives and how far it travels. The EHX XO Stereo Electric Mistress adds a Color Blend control and chorus mode. These are genuinely different instruments with different voices; neither is “better” in the absolute sense, but the M117R consistently wins on control precision and the documented heritage connection to Van Halen’s actual recordings.

The Boss BF-3 Flanger at $99–129 is the digital alternative. It has more voices (Standard, Enhancer, Gate/Pan, Bass), tap tempo on some modes, stereo output, and a lower price. What it doesn’t have is the analog warmth of the BBD circuit — digital flangers tend to sound cleaner and crisper where analog flangers sound denser and more organic. Players who want the M117R’s character and have heard the difference in a direct comparison rarely reach for the BF-3. Players who want flanger functionality at minimum cost with maximum flexibility should consider it.

Buying Guide and Ownership Notes

The M117R retails at $199.99 MSRP with street prices in the $150–180 range new in 2026. Used examples in excellent condition typically trade between $80 and $130. This is a well-built pedal that holds its value — it was selling for similar prices in the mid-2010s, and the demand hasn’t eroded. Budget buyers should feel confident about used purchases: the M117R is robust, the circuit is simple, and there are no exotic or hard-to-source components. If the BBD chip fails, a competent tech can source a replacement from the analog pedal parts ecosystem. The main thing to verify on used units is that the Regen and Width knobs turn smoothly through their full range without scratching or intermittent drop-out — pot replacement is inexpensive, but crackly pots on a used pedal are a negotiating tool.

The 18V power requirement is the most common ownership gotcha. Budget for an appropriate power supply if you don’t already have an 18V output on your board. The Dunlop DC Brick ($79 street) is the most natural companion, and it has enough 9V outputs to handle the rest of a typical MXR-heavy pedalboard simultaneously. The Mini Iso-Brick has a single 18V output rated at 250mA — the M117R uses 39mA of that, leaving ample margin for nothing, because the Mini Iso-Brick only has the one 18V port. Plan your power supply purchase around how many 18V pedals you’re likely to run alongside the M117R.

For vintage hunters: the original late-1970s MXR M-117 Flangers trade for $100–300+ depending on condition and provenance. The circuit in the M117R reissue is faithful enough that most players won’t hear a meaningful difference, but collectors value the original for historical reasons and the variable character of aging components. The most significant practical difference is bypass: older MXR units used a buffered bypass circuit that some players find affects their signal chain’s character. The M117R uses true hardwire bypass, which has no tonal influence on the dry signal path when the pedal is off.

Who Should Buy the MXR M117R Flanger

The M117R is the right pedal for three distinct buyer profiles. First: players who specifically want the analog flanger sound that defined Van Halen’s classic recordings and understand that they’re buying a verified piece of that sonic heritage, not just a flanger that happens to be gray. The documented settings, the confirmed circuit history, and the actual recordings this pedal inspired are part of what you’re paying for. Second: players who want a full-featured, four-knob analog flanger with genuine Manual frequency control — the ability to stop the sweep and park the effect at a specific frequency is a practical advantage that most compact flangers don’t offer. Third: players who use both clean and high-gain sounds and want a single modulation pedal that handles both with equal effectiveness — the M117R’s wide Regen range and adjustable sweep depth mean it works as a gentle clean-channel shimmer and as a thrash metal aggressor, often with just Speed and Regen adjustments between the two applications.

It’s not the right pedal if you’re primarily looking for chorus or vibrato — those effects have dedicated tools that do them better. It’s also not right if space and budget are the primary constraints; the M152 Micro Flanger handles the same general sonic territory in a smaller, cheaper package, with the trade-off being the loss of the Manual control and the full depth of the sweep customization. The M117R is a specialist’s choice within the flanger category — the most capable implementation of the analog BBD flanger principle that MXR makes, at a price that reflects its pedigree and capability.

Frequently Asked Questions