The ThorpyFX Chain Home is a tremolo and boost pedal that recreates the Vox Repeat Percussion, a deep, choppy, sawtooth-wave tremolo that Vox originally sold as a plug-in effect and built into guitars12. Where the vintage circuit had a fixed, narrow character, the Chain Home gives it a much expanded speed range through its Rate knob, and it carries an onboard boost to solve the volume drop that this style of tremolo can cause1.
The pedal first appeared in 2016 as Thorpy's Chain Home Tremolo, and in 2017 it became the first release in founder Adrian Thorpe's Reimagined Series of retro-inspired pedals34. Around 100 units were made in the larger original MKI format5. In August 2025 ThorpyFX brought it back permanently as a smaller MKII Special Order edition with the same circuit5.
What it does to your sound
The Chain Home is based on the old Vox Repeat Percussion effect, a tremolo whose sawtooth waveform gives a very distinctive choppy, percussive attack rather than the smooth swell of a typical sine-wave tremolo1. Premier Guitar described the original Vox effect as "a deep, choppy, sawtooth-wave tremolo"2, and gearnews characterized that choppy, gate-like quality as the sound players seek from Repeat Percussion-style circuits2.
Two controls shape the effect:
| Control | What it does |
|---|---|
| Rate | Sets the tremolo speed, with a much expanded range over the original Vox Repeat Percussion1 |
| Depth | Sets the depth of the tremolo; at minimum the pedal works as a pure booster1 |
The boost side is the High Headroom Dane Smooth Boost, built with 2.9V Zener diodes. It was developed for the Chain Home specifically to remedy the volume drop that this kind of tremolo circuit produces, and it later became the basis for other ThorpyFX boost designs4.
"If you turn the trem Depth to minimum, you can use the pedal as a pure booster, with or without tonal shift."
That makes the Chain Home a two-in-one: a percussive tremolo and a standalone boost pedal on one board space1.
The MKI and the MKII Special Order edition
The original MKI Chain Home came in one of Thorpy's familiar tank-like metal enclosures, with green-painted flanks, at 145 x 70 x 60 mm3. Only around 100 units were made in that larger format5.
The MKII, revived in August 2025, is a significant change in form rather than circuit5:
- Same circuit as the larger MKI Chain Home5
- Smaller enclosure format5
- Additional controls for more range, adaptability and versatility5
- Sold as a Special Order item in the Special Projects section of the ThorpyFX website5
- No Order Window limit; permanently available in the catalog5
- Made in small batches once or twice a month, approximately 2 weeks to ship from order5
The MKII is built to order in small batches, so expect roughly a two-week wait between ordering and shipping. No new demos accompany the revived release; the earlier MKI demos by Andy Martin and Mike Hermans, which show the same circuit, still apply5.
Guitar Pedal X describes the MKII as "a significant evolution and enhancement over the Vox Repeat Percussion Tremolo on which it's based"5.
Power, bypass and build
The Chain Home runs on a 9-volt mains supply or a battery, with the battery not supplied, and it is true bypass3. It is made in the UK3.
What reviewers said
MusicRadar's Trevor Curwen reviewed the pedal and summed it up as:
"A winning two-in-one combo: quirky, rare vintage trem coupled with a great-sounding booster."
guitar.com's Richard Purvis reviewed the original MKI in March 2017, noting the tank-like enclosure and the UK build3. In Guitar Pedal X's round-up of the best new modulation pedals of 2025, the Chain Home was listed as the "Supremely Choppy Tremolo (Vox Repeat Percussion)" at £215 / $2446.
Videos
ProGuitarShopDemos
ThorpyFx
Mike Hermans
Questions
Is the ThorpyFX Chain Home true bypass?
Yes. The guitar.com review of the original Chain Home lists true bypass among its features, alongside 9-volt mains or battery power. With the pedal off, your signal passes through without buffering or coloration.
Can the Chain Home run on a battery?
Yes, it can be powered by a 9-volt mains supply or a battery, though the battery is not supplied with the pedal. You will need to provide your own if you want to run it off-grid from a power supply.
Can you use the Chain Home as just a boost pedal?
Yes. MusicRadar's reviewer notes that turning the tremolo Depth control to minimum lets you use the pedal as a pure booster, with or without a tonal shift. The onboard Dane Smooth Boost circuit was added to remedy the volume drop typical of this kind of tremolo.
Where is the ThorpyFX Chain Home made?
The original Chain Home was made in the UK, housed in one of ThorpyFX's tank-like metal enclosures with green-painted flanks. It was the first pedal in founder Adrian Thorpe's Reimagined Series of retro-inspired designs.
How long does the Chain Home MKII take to ship?
The MKII is a Special Order item made in small batches once or twice a month, so it takes approximately two weeks to ship from placing your order. There is no Order Window limit; it is permanently available in the catalogue.
Sources (6)
- ThorpyFX Chain Home review, MusicRadar, 2017-07-03
- Magnetic Effects Electrochop Review, Premier Guitar, 2013-09-07
- ThorpyFX Chain Home Tremolo Review, guitar.com, 2017-03-29
- Guitar Pedal X, Guitar Pedal X, 2024-04-08
- Guitar Pedal X, Guitar Pedal X, 2025-08-11
- Guitar Pedal X, Guitar Pedal X, 2025-12-09