The JAM Pedals "Butteskull" Tubedreamer is an overdrive pedal with custom artwork: a one-of-a-kind, hand-painted version of the TubeDreamer mk.2, the Greek maker's 808-style overdrive. JAM describes the mk.2 as "a warm, rich and articulate 808-style overdrive built to cut through a mix without ever sounding" congested or harsh1. The Butteskull version carries the same circuit, with the artwork as the only difference: JAM's own wording is "Same sound, different artwork"2.
The circuit and what it does
At its core is what JAM calls "the legendary JRC4558D chip, paired with three-diode asymmetrical clipping for natural response to picking" dynamics2. That is the classic 808-style formula, the same family of circuit as the Tube Screamer, and JAM has been building its own take on it for years. The mk.2 generation, released in May 2026, added two things the earlier TubeDreamer did not have: a no-diode clipping option and a second footswitch for high gain32. Gearnews, covering the launch, described it as JAM revamping "its super popular TS-style pedal with a host of new features and sounds"4.
The clipping toggle is the heart of the mk.2's flexibility. It selects between two voices23:
- Asymmetrical mode: three diodes in the clipping stage, which JAM says gives "classic warmth, touch sensitivity and harmonic texture"2
- No-diode mode: the diode clipping is removed entirely, for what JAM describes as "a more open, dynamic and amp-like feel with extra headroom" and greater clarity2
Players who know the 808 sound can think of the toggle as choosing between the familiar compressed, mid-focused drive and a more open, less clipped version of the same core circuit2.
Controls and footswitches
| Control | What it does |
|---|---|
| Level | Controls output level2 |
| Tone | Adjusts tonal balance2 |
| Gain | Sets the amount of drive2 |
| Clipping toggle | Selects asymmetrical or no-diode operation2 |
| HIGH GAIN footswitch | Activates an additional gain stage2 |
| Engage/Bypass footswitch | Turns the pedal on and off3 |
The HIGH GAIN footswitch is the mk.2's other addition. JAM explains: "The dedicated HIGH GAIN footswitch activates an additional gain stage. Two internal trimmers set its output independently" for asymmetrical and no-diode modes, which means you can match the boosted level to the normal sound or set it as a deliberate boost2. Guitar Pedal X, covering the release, listed the full control set as "Level, Gain, Tone, Clipping : Asymmetrical / No-Diode, High Gain Footswitch, Engage/Bypass Footswitch"3.
On the earlier TubeDreamer, high gain was on a toggle switch. The mk.2 moved it to a second footswitch, so it can be switched live mid-song3.
Power and setup
The pedal runs on 9V DC, center-negative, and draws 60 mA2. That is standard pedalboard power, well within what a typical isolated supply provides, but it is beyond a battery, so plan a power supply output for it. True bypass switching means it stays out of your signal path when off2.
The custom artwork, and buying one
The Butteskull is one of several artwork versions of the mk.2 that JAM offers, alongside the "Astronaut-y", "Blood Spatter", "Celestial Window" and "Monterey" Tubedreamers2. JAM is direct about what a buyer gets: "Every custom artwork pedal is a one-of-a-kind hand-painted piece. The pedal you receive will differ in detail from the p"hotos shown2. In other words, the photos are representative, not a specification.
The listed price is £309.00 GBP with tax included2. JAM ships it DDP, with "20% UK VAT and all duties included. No extra charges on delivery," and shipping is free2. There is also a 30-day money-back guarantee with a refund, no questions asked2.
Sources (4)
- TubeDreamer, JAM Pedals (www.jampedals.com)
- “Butteskull” Tubedreamer, JAM Pedals (jampedals.com)
- Guitar Pedal X, Guitar Pedal X, 2026-05-14
- JAM Pedals TubeDreamer MK2: More Tube Screamer than a Tube Screamer?, gearnews.com, 2026-05-15
