Chase Bliss Preamp MKII

The Chase Bliss Preamp MKII, also known as the Automatone Preamp MKII, is an analog preamp pedal that covers boost, overdrive and fuzz in one box, with a parametric midrange EQ and 30 presets. Chase Bliss calls it the "Do-it-all of drive, filtering, and fuzz." Every control is connected to a digital brain, but the signal path stays 100% analog¹. It was built in collaboration with Chris Benson of Benson Amps, and billed as "the first Automatone"².

Boost, drive and fuzz in one analog pedal

The pedal spans a wide gain range. JHS Pedals' buying guide describes what it does in plain terms: "This pedal does everything: boost, light overdrive, medium overdrive, heavy overdrive, scorched earth, fluffy clouds"⁶. Pedal of the Day found it "possible to conjure up clean boost, overdrive, fuzz and wonderful tone-shaping EQ settings in a heartbeat"⁷.

The fuzz side has two characters. Chase Bliss describes the Open setting as "classic, powerful, and massive," while Gated gives "a squished, zippy, and penetrating" sound¹. Fuzz gain, level and gate threshold can be adjusted internally, but you have to open up the pedal to do it⁸. A variable diode clipping control selects transistor-only, silicon, or asymmetrical germanium clipping².

The controls and motorized faders

The pedal's signature feature is its motorized faders, which physically move to match preset changes and external control signals¹. Guitar World's roundup noted that the faders for EQ, volume and gain "physically adjust to match saved presets, delivering instant visuals of your settings"⁹. The sliders set Volume, Gain, Treble and Bass, plus two sliders dedicated to the midrange⁷.

Depending on the Scroll setting, presets are organized as 3 banks of 2, 4 or 10 presets¹¹. The enclosure is brushed, anodized metal with wood accents².

Presets, MIDI and expression

The pedal holds 30 internal presets and supports MIDI, CV and expression control¹. MIDI mirrors the presets, porting presets 0 to 29, and adds CC functions including independent Volume and Gain adjustment and an LFO oscillator on the mids frequency control¹². Expression comes in on CC#100, with a range of 0 to 127¹³.

The pedal ships on MIDI channel 2¹³. To change it:

1. Hold down both stomp switches while applying power.
2. Release them once the seven-segment display lights up.
3. The pedal sets itself to the channel of the first Program Change message it receives¹³.

On preset switching, Chase Bliss support is direct: "The best way to ensure you're pop-free is to briefly pause while you change presets"⁸.

Power and connections

The Preamp MKII runs on 9V DC, center negative, at roughly 500 mA¹. That current draw rules out a standard battery and means it needs a dedicated output on most isolated supplies rather than a shared daisy chain. Internally, the power supply boosts the voltage up to 30V, a design Chase Bliss later reused in the Condor Hi-Fi¹⁴. Input impedance is 1 megaohm, unless the fuzz is engaged, which switches to a low-input impedance "because it sounds nice"¹.

A Chimera amp front end, built with Benson Amps

The circuit is built around the front-end circuitry of Benson Amps' Chimera tube amp, substituting FET transistors for the amp's 12AX7 triode stages¹. Delicious Audio describes the recipe as combining "the DNA of Benson Amps' Chimera in a box Preamp with a little fuzz, some of Condor's resonant parametric mids"¹⁰. Guitar Pedal X frames it as the MKII version of the original Benson Amps Preamp pedal, with the Benson preamp itself based on a transistorized version of the Chimera 30-watt amp¹².

The project took about a year from its first preview at NAMM in January 2019⁵. It was announced at NAMM 2020 with a full production run expected that May³, and by July 2020 it was available at $749⁴. Within months, over 1,000 units had been sold¹⁵.

What reviewers said

Reception was strong. Guitar World reported the pedal "was seen as a game-changer upon its release, and made its way onto a number of big-name pedalboards"¹⁶. On That Pedal Show, the presenters went further:

In an earlier That Pedal Show episode comparing it against the Klon, King of Tone and Fuzz Face among others, they said "Chase Bliss and Benson have done something extraordinary with the Automatone MkII"¹⁸. JHS Pedals scored it 5 out of 8 on its checklist but wrote that "in my heart the Automatone MKII Preamp deserves 8/8" and that it is "worth every dime" at $750⁶. Pedal of the Day took a measured view of the price: "While the price tag may be a bit steep for some, it's pretty much 5 pedals in one"⁷. Guitar.com's launch coverage called it "definitely not for the light-hearted," while allowing that die-hard enthusiasts would find the novel concept hard to resist².

The Knobs channel published a sponsored demo showing the pedal's distortion shape on an oscilloscope, walking through its drive character and external control options¹⁹.

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That Pedal Show also compared it head to head with classic drives and fuzzes in a full demo video¹⁷.

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Videos

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Questions