PastFx Elastic Mattress

The PastFx Elastic Mattress is an analog flanger pedal from Australian maker PastFX, built as a recreation of the mid-to-late-1970s "V2" version of the Electro-Harmonix Electric Mistress, the 18-volt original rather than the later 9-volt reissues¹². PastFX describes it as capturing the lush yet articulate base and swooshing glitz of the original Mistress, with slightly less saturation and better note definition than later Electric Mistress models, and capable of more subtle, chorusy flanging¹. The V2 circuit it copies is the one famously used by David Gilmour, live and in the studio, both as a solo artist and with Pink Floyd¹.

Like the original, it runs on 18 volts, uses a NOS Matsushita / Panasonic MN3007 bucket brigade device as its analog delay line, and carries the Electric Mistress's signature Filter Matrix mode alongside normal flanging¹².

What it does to your sound

A flanger mixes a short, continuously swept delay with your dry signal to produce the jet-like sweep the effect is known for. The Elastic Mattress follows the Electric Mistress approach: PastFX characterizes the result as liquidy, gracefully modulated tones, and Delicious Audio's profile of the pedal says it can get funky, trippy and wild when pushed¹².

Because the circuit is the earlier V2 design rather than a later Electric Mistress revision, PastFX positions it as the brighter, more articulate end of the Mistress family. Guitar Pedal X's Stefan Karlsson, who owns multiple versions, calls the V2 iteration "Bright & Sparky" and says it lets you get the most out of that typically bright and sparkly flanger sound²⁵.

The controls and Filter Matrix mode

The control set mirrors the original Electric Mistress and adds a blend knob the vintage pedal never had¹²⁴.

Filter Matrix mode is the Electric Mistress's classic trick: it stops the oscillator and lets the Range knob set a fixed delay amount, generating static phase cancellations, comb-filter sounds that sit still rather than sweep². PastFX notes this is the standard EM Matrix feature, accessed by switching the toggle right toward the blue LED¹.

The current version also adds an internal bass cut control, fully clockwise for stock response and turned counterclockwise to reduce bass, plus an external brightness control¹.

Power: 18V DC, 25mA

The Elastic Mattress needs an 18V DC center negative supply and draws 25mA¹. There is no battery option¹. That 18V requirement matters: it is what the original V2 Mistress ran on, and it rules out a standard 9V output. Premier Guitar notes that while more recent examples of the EHX Electric Mistress Flanger/Filter Matrix run on 9V, the original versions were 18V⁶. You will need a power supply with an 18V output, not a typical daisy chain.

The pedal uses Neutrik instrument jacks, with PastFX stating the audiophile-grade parts are sourced from MMK, Wima, Epcos, Vishay, Panasonic and Nichicon¹. Delicious Audio's 2022 profile also lists a Lumberg DC jack².

History: the V2 Electric Mistress and the PastFX versions

The original Electro-Harmonix Electric Mistress dates to the 1970s, and JHS Pedals' modulation guide calls it "a great flanger pedal, one of my all-time favorites"⁷¹. PastFX built the Elastic Mattress as its take on the mid-to-late-1970s 18V V2 version specifically, the Gilmour-associated circuit¹.

The pedal has gone through several iterations:

• Original version: The first Elastic Mattress, based on the vintage 70's EHX Electric Mistress, with internal volume and treble trimmers⁴.
• V2 (2022): Added stereo output and an external mini level knob, as part of PastFX's updated Flanger Trifecta alongside the Reticon and Hot for Flanger⁴.
• Current version: Adds stereo outputs (mono unchanged), a new internal bass cut control and an external brightness control¹.
• Deluxe Elastic Mattress (2025): A separate circuit based on the late-1970s and 1980s EHX Deluxe Electric Mistress, which Guitar Pedal X calls the 4th major iteration of the PastFX circuit⁸⁹.

Guitar Pedal X's pricing across the Trifecta updates listed the Elastic Mattress V2 at $299 AUD / $210 USD⁴, and the same $210 USD figure appears for the MN3007 version in the site's later coverage⁴¹⁰.

The Deluxe Elastic Mattress

The PastFx Deluxe Elastic Mattress is a related but distinct pedal: PastFX's spin on the Deluxe Electric Mistress that Electro-Harmonix made in the late 1970s and 1980s⁸. Guitar Pedal X's reviewer, who owns the V2 and V3 Elastic Mattresses, considers them different circuits and says the Deluxe completes the trifecta for him¹¹.

Where the standard Elastic Mattress draws 25mA, the Deluxe draws 160mA on the same 18V DC center negative supply, with no battery option; PastFX recommends Cioks DC7/4/8/10/SOL supplies⁸¹. The Deluxe adds a 70's/80's voicing pushbutton that switches between the early, darker filtering circuit and the lighter filtering of the classic "green" Deluxe Mistress, a +/- negative feedback pushbutton, and an internal high/low impedance switch, but it omits the stereo output port of its predecessor⁸⁹.

What reviewers said

Guitar Pedal X's Stefan Karlsson has covered the Elastic Mattress family repeatedly. Of the V2 update he wrote that the Elastic Mattress had possibly become the most special pedal in PastFX's flanger Trifecta, with its new stereo output, calling it the ultimate of this genre with no direct equivalent⁴. In later coverage he said both of his versions sound exceptional, with the second iteration getting the most out of the bright and sparkly flanger sound⁵.

Of the Deluxe, he reported that it sounded gorgeous from the start without any internal adjustment, and that he favors the Positive Feedback and 80's Lighter settings overall¹¹. Guitar Pedal X also gave the PastFX Deluxe Elastic Mattress a Silver award in its 2025 modulation pedals of the year roundup¹².

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