The Formula B EIGHTY Master is a tweakable amp-in-a-box distortion pedal from the Italian maker Formula B, built as a Marshall-style overdrive in the "MIAB" (Marshall in a Box) tradition1. Delicious Audio described it as "an organic and dynamoc distortion that responds to both touch and knob", meaning it cleans up and shifts character with your picking and your guitar's volume knob1. It is specifically billed as a JCM800 variety of MIAB, but Guitar Pedal X notes it covers Plexi sounds easily too2.
The pedal has gone through several editions. The original was a 1590BB mid-size edition pedal with toggle switches, including a 50W/100W gain structure switch and a 3-way Compression switch labeled Some, None and Lots3.
The controls: 50W/100W switch, compressor and 3-band EQ
The original Eighty Master carries the whole front end of an amp: a 3-band EQ section, a power selector and a compressor, all onboard1. The two toggles that set it apart are a 50W/100W gain structure switch and a 3-way compression switch labeled Some, None and Lots3.
The power toggle is a 2-way switch between two gain structures. Delicious Audio explains the difference13:
"the 50w mode delivers a dynamic and medium gain overdrive, while the 100w option offers more compressed and aggressive tones in the hi-gain realm."1
The compression switch works like a built-in squeeze control. In the central position it is off, so the pedal responds with maximum dynamics; the two outer positions dial in more or less compression1.
The V2 rethinks the layout. Where the original used a 50W/100W gain structure toggle342, the V2 gives you Gain 1 and Gain 2 controls, two gain channels you can switch between with the CH1/CH2 footswitch, alongside Volume, Modeling (Presence), Bass, Mids and Treble4.
The full V2 control layout:
| Control | What it does |
|---|---|
| Volume | Output level |
| Gain 1 | First gain channel |
| Gain 2 | Second gain channel, in place of the original's 50W/100W switch3 |
| Modeling (Presence) | Presence-style top-end shaping |
| Bass | Low-band EQ |
| Mids | Mid-band EQ |
| Treble | High-band EQ |
| CH1/CH2 footswitch | Switches between the two gain channels |
| Bypass footswitch | Engages and bypasses the pedal3 |
The V2's full control set is Volume, Gain 1, Gain 2, Modeling (Presence), Bass, Mids and Treble, plus CH1/CH2 and Bypass footswitches4.
Versions and pricing
| Version | What distinguishes it |
|---|---|
| Eighty Master (original) | 1590BB mid-size enclosure with toggle switches, including a 50W/100W gain structure switch and a 3-way Compression switch (Some / None / Lots)3 |
| Eighty Master V2 | Volume, Gain 1, Gain 2, Modeling (Presence), Bass, Mids, Treble, CH1/CH2 footswitch, Bypass footswitch4 |
The change between the original and the V2 is in the controls and the enclosure rather than the concept: the original is a 1590BB mid-size pedal with toggle switches3, while the V2's layout is Volume, Gain 1, Gain 2, Modeling (Presence), Bass, Mids, Treble and two footswitches34.
What reviewers said
Reviewers were consistently positive across every edition. Of the original 1590BB version, Guitar Pedal X's Stefan Karlsson wrote435:
"I already proclaimed it to be one of the most instantly satisfying 'Marshall in a Box' pedals that I have encountered"3
In a best-of roundup he called it "One of my favourite all-time MIAB pedals - just instant satisfaction and killer tones every which way"5. On the V2 Compact, he found "a wonderfully authentic and properly snappy and elastic core Marshall Voicing", and noted that it covers JCM800, Plexi, Hot-rodded Modded and Brown Sound tones3. Of the MIAB V2 he wrote: "This is one of the most insanely satisfying MIAB pedals - so easy to dial in, and so easy to get superior sounds"2. And in a Marshall-pedal buying guide he summed up the V2 as having "an insanely appealing core tonality with everything at Noon - a really smart 2-channel Marshally type" overall4.
Videos
The GasTube
Brett Kingman
Kris Barocsi
Questions
What does the 50W/100W switch do on the Formula B Eighty Master?
It is a 2-way toggle that selects between two gain structures. The 50W mode delivers a dynamic, medium-gain overdrive, while the 100W option gives more compressed and aggressive high-gain tones. On the V2 Compact edition this switch is replaced by Gain 1 and Gain 2 knobs, giving you both gain structures as switchable channels.
Where is the Formula B Eighty Master made?
It is made in Italy. Formula B is an Italian effects maker, and the Eighty Master was described by Delicious Audio as hailing from Italy when the pedal was first written up in March 2023.
How much does the Formula B Eighty Master cost?
Prices vary by version and date. The original was listed at €255 / £225 in December 2023, the V2 Compact at €199 in the EU and £189.99 in the UK in August 2024, and the Eighty Master V2 Twin Channel Preamp at €229 / $249 / £194 in November 2025.
What does the middle position of the compression switch do?
The original Eighty Master has a 3-way compression switch labeled Some, None and Lots. In the central position the compressor is off, so the pedal responds with maximum dynamics. The two outer positions add progressively more compression to the tone.
Sources (5)
- Formula B EIGHTY Master, Delicious Audio, 2023-03-20
- Guitar Pedal X, Guitar Pedal X, 2024-12-17
- Guitar Pedal X, Guitar Pedal X, 2024-08-09
- Guitar Pedal X, Guitar Pedal X, 2025-11-21
- Guitar Pedal X, Guitar Pedal X, 2023-12-16
