The Electro-Harmonix Mod Rex is an Electro-Harmonix chorus pedal, currently around $159.28. Close alternatives include the Electro-Harmonix Worm and the Henretta Engineering H-Bomb Trembrato. It pairs well with the Fender Twin Reverb Head and the Boss BD-2 Blues Driver.
Electro-Harmonix Mod Rex
Electro-Harmonix · pedal
The Electro-Harmonix Mod Rex is a polyrhythmic modulator pedal from Electro-Harmonix, delivering four simultaneous modulation types (tremolo, vibrato, filter, and panning) each with independent polyrhythmic sequencing at different rates. The Mod Rex allows each modulation type to run at its own tempo subdivision for complex polyrhythmic modulation textures that evolve continuously. Controls include individual Rate and Depth for each modulation type plus a Master Rate.
What stands out
“The Mod Rex delivers polyrhythmic modulation combining tremolo, vibrato, filter, and panning at independent polyrhythmic rates for continuously evolving, complex modulation textures suited for experimental, ambient, and progressive players …”
— from the community notes
“The Electro-Harmonix Mod Rex is a polyrhythmic modulator pedal from Electro-Harmonix, delivering four simultaneous modulation types (tremolo, vibrato, filter, and panning) each with independent polyrhythmic sequencing at different rates”
— from the listing
“the mod rex allows each modulation type to run at its own tempo subdivision for complex polyrhythmic modulation textures that evolve continuously”
— from the listing
“Its standout strength is the polyrhythmic multi-modulation with four independent modulation types running at different rhythmic subdivisions”
— from the community notes
“Four-modulation combination is highly specialized for experimental and ambient applications”
— from the reviews
Trade-offs
“In the signal chain modulation sits after drive and before reverb”
— from the community notes
- tremolo
- modulation
- filter
- vibrato
- complex
- ambient
- experimental
- four simultaneous modulation types
Price updated Oct 24, 2026
Genres the Electro-Harmonix Mod Rex is commonly used in
- Ambient
- Experimental
- Electronic
cited
Inferred from shared tonal signals, not a stated genre tag. - Post Rock
cited
Inferred from shared tonal signals, not a stated genre tag. - Indie
cited
Inferred from shared tonal signals, not a stated genre tag. - Shoegaze
cited
Inferred from shared tonal signals, not a stated genre tag.
Amps that pair well with the Electro-Harmonix Mod Rex
Pedals that stack with the Electro-Harmonix Mod Rex
Boss BD-2 Blues Driver
Boss
7% matchBoss BD-2 Blues Driver leans toward full, and that's a real, usable character to pair with
Comes earlier in the signal chain
Catalinbread Giygas
Catalinbread
7% matchWhat Catalinbread Giygas brings here leans toward octave — that's worth building a pairing around
Comes earlier in the signal chain
EarthQuaker Devices Dispatch Master V2
EarthQuaker Devices
6% matchKeep EarthQuaker Devices Dispatch Master V2 after Electro-Harmonix Mod Rex in the signal chain, where it won't crowd Electro-Harmonix Mod Rex — goes in the amp's FX loop (or last, into a clean amp)
Comes later in the signal chain
Electro-Harmonix Holy Grail Max
Electro-Harmonix
6% matchRun Electro-Harmonix Holy Grail Max after Electro-Harmonix Mod Rex in the signal chain, where it won't crowd Electro-Harmonix Mod Rex — goes in the amp's FX loop (or last, into a clean amp)
Comes later in the signal chain
Cheaper alternatives
Marshall VT-1
Marshall
58% similarityShared character: vibrato, tremolo, modulation
Mr. Black Downward Spiral
Mr Black
58% similarityShared character: tremolo, ambient, modulation
Boffin FX Vibratron
Boffin Fx
56% similarityShared character: vibrato, tremolo, modulation
JHS Tidewater Tremolo
JHS Pedals
54% similarityShared character: tremolo, modulation
Behringer UT300
Behringer
91% similaritysimilar tone character
FTelettronica Satellite Tremolo
Ftelettronica
91% similaritysimilar tone character
Boutique & premium upgrades
Carl Martin TremO'vibe
Carl Martin
63% similarityShared character: vibrato, tremolo, modulation
Old Blood Noise Endeavors Blackcap Asynchronous Dual Tremolo
Old Blood Noise Endeavors
62% similarityShared character: tremolo, ambient, overdrive
SolidGoldFX Aurras
Solidgoldfx
54% similarityShared character: vibrato, ambient, modulation
Old Blood Noise Endeavors Blackcap Harmonic Tremolo
Old Blood Noise Endeavors
51% similarityShared character: tremolo, ambient
Alexander Pedals Equilibrium DLX Vintage Modulation
Alexander Pedals
51% similarityShared character: vibrato, tremolo, modulation
Cusack Music Tap A Whirl V2
Cusack Music
91% similaritysimilar tone character
Similar charactersee all similar tone character →
Electro-Harmonix Worm
Electro-Harmonix
68% similarityShared character: vibrato, filter, tremolo
Henretta Engineering H-Bomb Trembrato
Henretta Engineering
68% similarityShared character: vibrato, tremolo, modulation
Dreadbox Treminator
Dreadbox
58% similarityShared character: tremolo, modulation, reverb
JHS Kodiak
JHS Pedals
56% similarityShared character: tremolo, ambient, modulation
ZVEX Vibrophase
Zvex
56% similarityShared character: vibrato, tremolo, modulation
MXR Tremolo M305
MXR
55% similarityShared character: tremolo, ambient, modulation
See all alternatives to the Electro-Harmonix Mod Rex (cheaper + boutique) →
Questions people ask
What are good alternatives to the Electro-Harmonix Mod Rex?+
The closest matches in character are the Electro-Harmonix Worm, the Henretta Engineering H-Bomb Trembrato, the Dreadbox Treminator. Budget picks: Marshall VT-1, Mr. Black Downward Spiral, Boffin FX Vibratron. Boutique upgrades: Carl Martin TremO'vibe, Old Blood Noise Endeavors Blackcap Asynchronous Dual Tremolo, SolidGoldFX Aurras.
What pairs well with the Electro-Harmonix Mod Rex?+
Strong matches from rig and tone-complementarity evidence: Fender Twin Reverb Head, Boss BD-2 Blues Driver, Catalinbread Giygas — What Fender Twin Reverb Head brings here leans toward dynamic — that's worth building a pairing around.
How much does the Electro-Harmonix Mod Rex cost?+
Around $159.28 (live listing price, updated Oct 24, 2026).