The VFE Merman is a transparent overdrive pedal from VFE Pedals, the builder run by Peter VonRutter of VonRutter Family Effects. It takes the Klon Centaur circuit as its starting point: VFE's own project document calls it "a Klone-like pedal with classic VFE style tweaking," and Pedal of the Day described it in 2015 as "an impressive klone-like overdrive"12. What sets it apart from most Klones is that where an original Klon uses a dual-ganged pot to blend the dry and dirt signals, the Merman splits that into two independent controls, so you can blend the dirt more subtly behind the clean boost path1.
The pedal is discontinued. It carried a list price of $1993, and by 2019 second-hand examples were running around £250 on Reverb4. After the VFE pedal line ended, the actual circuit boards used to build it were released for DIY use only, with the project document hosted by Madbean Pedals1.
A Klon-style overdrive with split blend controls
The Klon Centaur's signature is a clean boost path summed with a clipped drive path, blended by a dual-ganged pot so both halves move together. The Merman keeps the basic Klon elements but separates them: instead of the dual-ganged pot, the drive signal path and the dry path each get their own control1. Pedal of the Day's reviewer, Mike B, highlighted this as the pedal's core idea, noting VFE "has come up with a way to control each of the sections that the signal gets split into individually," giving more control than an original Klon2.
In use, the reviewer found the Drive knob goes "from a sweet clean boost to a slightly distorted tone, with the ability to really drive your amp," replicating what the Klon's Drive knob does2. His overall verdict:
"A really great replication (with way more options) of an original Klon pedal, at about 1/10 of the cost."
Guitar Pedal X's Stefan Karlsson reached a similar conclusion in 2025, calling it "a fantastic Klone take" whose additional controls make it "more dynamic and vibrant than most equivalent or stock Klones"3. He also flagged the version to look for on the second-hand market: the V2 Silhouette Series with three big and three small knobs3.
The controls
The Merman has six knobs: three large (Drive, Level, Treble) and three small (Comp, Warm, Bottom)3. The small pots on VFE pedals of this era were 9mm types5.
| Control | What it does |
|---|---|
| Drive (large) | Sets the gain of the drive signal path; works with Comp to set the level of harmonic saturation1 |
| Level (large) | Output volume3 |
| Treble (large) | High-frequency content3 |
| Comp (small) | Compression; works with Drive for harmonic saturation1 |
| Warm (small) | Warm dry level, the dry-path side of the blend3 |
| Bottom (small) | Low-frequency roll-off / resonance3 |
The Warm and Bottom knobs are where the split-blend design pays off. Because the dry path has its own level control, you can set how much clean signal sits under the dirt independently of the drive gain. Pedal of the Day found that "the Drive, Warm and Bottom knobs work in conjunction with one another to form an incredibly thick yet transparent sound"2.
There is also a hidden seventh control: the schematic includes a 5k attack trimpot, which one commenter read as a way to tame the level with humbuckers5. That trimpot is the other half of what, in a Klon, is the dual-gang drive pot; VFE split the two halves into separate controls5.
Power and connections
The Merman runs on a standard 9V DC supply; the project document's voltage measurements were taken with a 9.42vDC One Spot1. Current draw is 15mA bypassed and 23mA engaged1. Internally, the circuit uses two TL072 op-amps, a TC7662B charge pump (which raises the internal headroom above what the 9V input alone provides), two 1N34A germanium diodes and two 1N5817 diodes1.
For DIY builders: the charge pump choice matters. One builder reported high-pitched whine with ICL7660S and MAX1044 chips that was cured by fitting the specified TC7662B: "I got some TC7662B's in the mail from Banzai and kicked out the 7660S; no more high-pitch whine, super quiet now"5.
The DIY afterlife
Because the Merman is discontinued, the practical route to one today is the DIY path. Madbean Pedals hosts the project document, and the PCBs are the actual boards used to build the discontinued VFE line1. The terms are strict: the projects are for DIY use only and may not be used commercially, including selling completed pedals or kits1. Guitar FX Layouts published a vero layout for the Merman in August 20165.
Builder reports from that thread are mixed but mostly positive. Hozy31 verified the layout and wrote: "Sounds quite different to my Klon but in a nice way. Very tweakable for sounds"5. A later builder, Jupnitski77, got a basically working build but reported the drive crackling with Compression fully counterclockwise when hitting the strings hard, and found the Warm and Bottom pots mild at low Compression settings5.
VFE Pedals has stated it will close at the end of 2026, while continuing out-of-warranty repair service indefinitely. The final VFE overdrive, the Tiamat, ships as both a built pedal and a DIY kit before then.
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Questions
Is the VFE Merman a Klon clone?
It is based on the Klon Centaur circuit, and VFE's own project document calls it a Klone-like pedal. But the basic Klon elements are only part of the story: the Merman splits the Klon's dual-ganged dry and dirt blend pot into two separate controls, giving more subtle blending of the dirt signal behind the clean boost path than an original Klon offers.
Is the VFE Merman still made?
No. The Merman is discontinued, listed at $199 when it was available. After the VFE pedal line ended, the actual PCBs used to build the line were released for DIY use only, and Madbean Pedals hosts the project document. VFE Pedals itself has stated it will close at the end of 2026 while continuing repair service indefinitely.
What does the Comp knob do on the Merman?
Compression is one of the three small controls, alongside Warm and Bottom. It works with the Drive knob to set the level of harmonic saturation, and reviewers found the Drive, Warm and Bottom knobs work together to form a thick yet transparent sound. At very low Compression settings, one DIY builder reported the drive stage crackling when hitting the strings hard.
Which charge pump IC works in the Merman build?
The project document specifies a TC7662B charge pump, alongside two TL072 op-amps, two 1N34A germanium diodes and two 1N5817 diodes. A DIY builder reported high-pitched whine with ICL7660S and MAX1044 substitutes that disappeared after switching to the TC7662B, so it is the one to use.
How much did the VFE Merman cost new?
Guitar Pedal X lists the discontinued Merman at $199 USD. By 2019 the same source noted second-hand examples around £250 on Reverb. As a point of comparison, Pedal of the Day described the original run as a really great replication of an original Klon pedal with way more options, at about one tenth of the cost.
Sources (5)
- Microsoft Word, Madbean Pedals, 2019
- VFE Pedals Merman Overdrive, Pedal of the Day (pedal-of-the-day.com), 2015-03-18
- Guitar Pedal X, Guitar Pedal X, 2025-09-03
- Guitar Pedal X, Guitar Pedal X, 2019-07-23
- Guitar FX Layouts: VFE Pedals Merman, Guitar FX Layouts (tagboardeffects.blogspot.com), 2016-08-19
