JPTR FX Warlow

The JPTR FX Warlow is a fuzz pedal built by the German boutique maker JPTR FX, which Chris Jupiter (Christian Lessenich) founded in 2016. JPTR FX calls it a premium-quality op-amp "Big Muff" pedal that has been painstakingly rebuilt to deliver an even bigger, wider sound with more gain and volume, and says it captures the raw, wild sound of the Seattle music scene¹. A Gate switch on the current version pushes the circuit into gated fuzz territory for nastier textures².

The pedal has sold for almost a decade and, in the words of the company's founder, has earned a following: "The Jive or Warlow for example pays my bills for almost a decade people love it it got a cult classic status"³.

A Big Muff-based fuzz with a gate switch

The Warlow's circuit is an op-amp Big Muff at heart. Op-amp Big Muffs, unlike the earlier transistor versions, use operational amplifiers for their gain stages, and JPTR FX says it rebuilt the circuit from a vintage "Big Muff" from the same release date as the Siamese Dream album¹. Delicious Audio describes the result in the maker's own terms as "our take and dedicated interpretation of an op-amp based, Pi-style fuzzstortion/distortiofuzz pedal"⁵.

What sets the Warlow apart from a stock Big Muff is its filter section. Pedal of the Day's review explains that it "combines both classic Muff and RAT filters for a truly versatile and dynamic" sound⁴, a lineage JPTR FX confirms on its own product pages¹. The pedal also uses high grade Burr-Brown chips and Germanium clipping diodes, which Delicious Audio credits with "a very pronounced low end"⁵.

The Gate switch is the other distinguishing feature. JPTR FX describes it plainly: "Now featuring a new Gate switch that puts the circuit into a ugly, snarling gated fuzz for even nastier textures"². In practice, a gated fuzz cuts the signal off abruptly rather than letting it decay, which suits choppy, aggressive riffs and eliminates trailing noise at high gain.

Delicious Audio notes the pedal's physical presence too: "the Warlow comes in an appropriately large enclosure for its equally huge tones"⁵. Pedal of the Day's verdict on its range:

Versions and limited editions

The Warlow has appeared in several forms over its run, from compact variants to a do-it-yourself circuit board⁶⁷⁸.

A few details worth knowing about the versions:

• The Deluxe Warlow adds the octave-up circuit from JPTR FX's Katastrophe pedal: "We've taken the most beloved feature of the Katastrophe and baked it straight into an upgraded version of the Warlow"⁹. It was listed as a pre-order at the time of this page's verification⁹.
• The TRVE WARLOW LIMITED 50 was a pre-order shipping in May, described by the maker as "THE WARLOW, REIMAGINED IN BLACK METAL DARKNESS," and is now sold out¹⁰.
• The 10th Anniversary edition marks 10 years of JPTR FX, which the maker sums up as "10 years of noise," with only 20 pedals finished in Analog Magenta¹.
• The DIY Warlow V1 PCB reproduces the original Warlow Version One, of which only 50 units were ever built⁷. JPTR FX recommends Burr-Brown chips alongside TAD or other high-grade boutique parts for the build, ships the board as a standard small padded letter, and provides no technical support for it⁷.

Where it came from

The Warlow is built by JPTR FX, a German boutique pedal maker⁴. The company sells every model directly, building each order in batches¹, and the Warlow itself has been sold for almost a decade, a status its maker describes as a cult classic¹³.

The Big Muff lineage the Warlow draws on has its own history of clones and interpretations. An independent circuit analysis describes the Sekova Big Muff as "a clone of a triangle Big Muff" and "a rare Japanese Big Muff clone made by Shin Ei"¹¹, one example of how the Electro-Harmonix design has been reworked by builders over the decades. The Warlow is JPTR FX's own op-amp take on that tradition.

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