Skip to main content
MusicRadar MusicRadar The No.1 website for musicians
UK EditionUK US EditionUS AU EditionAustralia SG EditionSingapore
Sign in
  • View Profile
  • Sign out
  • Artist news
  • Guitars
  • Controllers
  • Drums
  • Keyboards & Pianos
  • Guitar Amps
  • Music Gear Reviews
  • Synths
  • Software & Apps
  • More
    • Recording
    • DJ Gear
    • Acoustic Guitars
    • Bass Guitars
    • Tech
    • Tutorials
    • Reviews
    • Buying Guides
    • About us
More
  • Christine McVie's masterpiece
  • Macca vs Phil Collins
  • Music theory tricks
  • Kiss From a Rose
  • 95k+ free music samples
  • Yes
  1. Guitars
  2. Guitar Pedals

Review round-up: guitar synth pedals

News
By Alex Lynham
Published 24 July 2019

Transform your electric guitar into a synthesizer with these offerings from Keeley, Electro-Harmonix, Pigtronix and Seymour Duncan

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.

Analogue synthesis has, somewhat rightly, a fearsome reputation for complexity, with terms like LFO and VCO thrown around in abandon. 

Until recently, guitarists had to learn the keyboard before being able to utilise synthesiser tones, or resort to weird and wonderful gadgets like the Roland V Guitars, or external hex pickups.

Now, however, advances in tech have put synthesis in the hands of your average axe-slinger, with no external gubbins or jargon required... or so the manufacturers claim. 

We thought we’d put this to the test, so we’ve got four of the best analogue guitar synth pedals together to see if we can wrap our luddite minds around them. Synthtopia or epic fail? Let’s find out...

Page 1 of 5
Page 1 of 5
Keeley Synth-1

Keeley Synth-1

Inspired by the legendary Boss Slow Gear, the Synth-1 is an envelope filter with some added synth goodness. 

The ‘chaos’ switch adds octave artefacts and overtones - which leads us to assume it’s probably a feedback circuit of some kind – while the filter control is a band-pass for the wave generator. There’s options for triangle, sine and square waves, and also for using an expression pedal, for almost wah-like control of the filter. 

In terms of tone, it’s thick, fuzzy and particularly tasty in the triangle mode with a slow attack. With the blend all the way up, we could see how this could become a trusted studio tool. 

4 out of 5 

Page 2 of 5
Page 2 of 5
Electro-Harmonix Mono Synth

Electro-Harmonix Mono Synth

With a reasonably compact form factor and functional good looks, the EHX Mono Synth definitely has the cool points going for it even before we plug it in. 

From then on it’s hard to get our jaw off the floor. The ‘Nu Wave’ patch is pure Gary Numan, and has us Googling the tab for Cars; ‘Unison’ sounds like giant mechs battling over Tokyo; ‘XOX’ is a RATM-style bass synth envelope; ‘Ghost’ is organ-like; and ‘Tinker’ slightly chiptune-esque. 

Throughout, the tracking is not bad at all, so long as it’s the first pedal in the chain; certainly more than good enough for guitar or bass live.

5 out of 5

Page 3 of 5
Page 3 of 5
Pigtronix Mothership 2

Pigtronix Mothership 2

In terms of pure tracking, the Pigtronix is a staggering achievement. 

We spent a few minutes trying to wrong-foot it with bends and detunes by pushing the headstock and it reacted perfectly, so long as we stuck to single notes and not chords. It combines square, triangle and sub octave sine wave oscillators into a single heavily-customisable synth sound, with extra expression input and a dedicated sub output. 

We had the most fun in the octave and unison modes, but on the whole it’s easy to find good synth tones from this unit, even if the number of controls on the front is initially a bit overwhelming. 

4 out of 5

Page 4 of 5
Page 4 of 5
Seymour Duncan Fooz

Seymour Duncan Fooz

Our rule of thumb with gear is that we should be able to roughly work it out without the aid of the manual - after all, the intuitiveness of the guitar is half the fun, right? 

With the great power of the Fooz synth, fuzz, trem, filter and all, comes a complexity that does require some reading. However, once it’s dialled in it serves well as a filter and envelope follower with more than your usual array of tweakable parameters. 

Though it does do the auto-wah thing well, that’s essentially the one core sound on offer, even if it can be altered via the filter, trem, fuzz and wave- shape control on the LFO. 

3.5 out of 5

Page 5 of 5
Page 5 of 5
Alex Lynham
Alex Lynham

Alex Lynham is a gear obsessive who's been collecting and building modern and vintage equipment since he got his first Saturday job. Besides reviewing countless pedals for Total Guitar, he's written guides on how to build your first pedal, how to build a tube amp from a kit, and briefly went viral when he released a glitch delay pedal, the Atom Smasher.

Read more
MXR Textures Granular Synth Pedal
Guitars Introducing Textures, the granular synth pedal from MXR that dreamy ambient tones are made of
 
 
Electro-Harmonix Dual Op-Amp Big Muff Pi 2
Guitar Pedals Electro-Harmonix Big Muff Pi 2 Dual Op-Amp Fuzz review
 
 
Meris Ottobit X
Guitars Meris unveils the Ottobit X, a high-end purveyor of lo-fi guitar sounds inspired by the ‘80s
 
 
Stranberg x Jam Stik MIDI
Electric Guitars “Sounds you'll never have heard from a guitar before”: Strandberg x Jamstik Chameleon review
 
 
A worn, dirty pedalboard with a variety of different guitar pedals
Pedalboards Best pedalboards 2026: top choice 'boards for guitarists
 
 
A guitar VST running in Kontakt player on a computer
Plugins Best guitar VSTs 2026: Get the best simulated guitar tones for your next production
 
 
Latest in Guitar Pedals
Jam Pedals Tiny Amp Destroyer
Artists Stu Mackenzie and Jam Pedals team up to bring you the secret behind his KGWL guitar tone
 
 
Warm Audio Dirty Boy Jr Booster
Guitar Pedals “It starts out polite but then gets loud, dirty and nasty”: Warm Audio Dirty Boy Jr Booster review
 
 
MXR M226 Flanger/Doubler
Guitars MXR unveils the Flanger/Doubler pedal – BBD-driven analogue mojo for ‘70s and ‘80s flavours or fatter metal tones
 
 
HeadRush unveils Prime, “the most powerful, versatile, and realistic-sounding floorboard FX processor ever”
Guitars HeadRush rolls out Tone3000 integration and native support for NAM captures to its amp modellers
 
 
MusicRadar Guitar Gear Round-up July 2026
Guitars MusicRadar’s July 2026 guitar gear roundup: featuring Orange Amps, Harley Benton, Epiphone and more
 
 
MXR Textures Granular Synth Pedal
Guitars Introducing Textures, the granular synth pedal from MXR that dreamy ambient tones are made of
 
 
Latest in News
Jam Pedals Tiny Amp Destroyer
Artists Stu Mackenzie and Jam Pedals team up to bring you the secret behind his KGWL guitar tone
 
 
lucid
Tech Minimal Audio's Lucid is a granular powerhouse that could be a rival to time-tested tools like Output's Portal
 
 
The Killers. (Photo by Frank Mullen/WireImage)
Artists Brandon Flowers says that every major label passed on Mr Brightside
 
 
Drummer Frank Beard of ZZ Top performs onstage during Day 1 of the 2023 Stagecoach Festival
Drummers Frank Beard, ZZ Top drummer, dies aged 77
 
 
AI Font 3D in digital cyber space
Tech Nearly 40% of music released last month used AI
 
 
Rush andf Angine de Poitrine composite image
Bands "They're fantastic!": Rush’s Geddy Lee and Alex Lifeson give thumbs up to Angine De Poitrine
 
 

MusicRadar is part of Future plc, an international media group and leading digital publisher. Visit our corporate site.

Add as a preferred source on Google Add as a preferred source on Google
  • About Us
  • Contact Future's experts
  • Terms and conditions
  • Privacy policy
  • Cookies policy
  • Advertise with us
  • Accessibility Statement
  • Careers

© Future Publishing Limited Quay House, The Ambury, Bath BA1 1UA. All rights reserved. England and Wales company registration number 2008885.

Please login or signup to comment

Please wait...