The Cathedral is a stereo reverb pedal from Electro-Harmonix, marketed with the line "Divine reverb for mere mortals!" and the promise to "surround your music with the aria of divine presence"1. It builds on the company's Holy Grail series of reverbs and carries seven different reverb types plus a digital echo effect, according to Premier Guitar2. Electro-Harmonix discontinued it in 20201.
What it is and what it does
The Cathedral is a digital reverb pedal with true stereo inputs and outputs, 24-bit A/D and D/A converters, and eight programmable reverb styles that can be loaded and saved1. Premier Guitar described it as containing seven reverb types in addition to a digital echo effect, building on the Holy Grail series2. Guitar Interactive Magazine called it "the award winning Cathedral Stereo Reverb (nine different studio-quality programs)"3.
The pedal's signature trick is its infinite reverb: hold the tap tempo footswitch and the reverb freezes, sustaining as long as you hold it1. MusicRadar's reviewer praised the Infinite Reverb mode for sustained synth pad-esque sounds4.
The controls
The Cathedral's front panel carries a white control knob (an encoder) alongside black control knobs, plus a Tap/Freeze footswitch5. Pedal of the Day walked through the knobs in its review6:
| Control | What it does |
|---|---|
| Blend | Mixes your dry signal with the Cathedral's reverb effect6 |
| Reverb Time | Adjusts the overall length of the effect6 |
| Tone / Dampening | Further sonic control and refinement over the pedal's sound6 |
| Feedback | Controls how long the reverb lingers after you play a note or chord6 |
| Pre-Delay | Sets when the effect kicks in relative to your playing6 |
The pre-delay section is set by tap tempo, using the Tap / Infinite footswitch in the bottom left corner of the pedal16. A Damping/Tone control is available for each reverb mode1. Premier Guitar summed up the operating scheme: "Topped off with a tap tempo mode and the ability to save up to eight presets, the Cathedral is definitely one intuitive device."2
The reverb modes
The Cathedral offers eight modes: Grail Spring, Accu Spring, Hall, Room, Plate, Reverse, Grail Flerb and Echo1. Pedal of the Day broke down where they came from and what each does6:
- Grail Spring: the spring reverb taken from the Holy Grail reverb pedal6
- Accu Spring: a new Accutronics spring tank emulation6
- Hall, Room, Plate, Reverse: what the reviewer called "top notch, professional reverb algorithms"6
- Grail Flerb: the Holy Grail Flerb with greater adjustability6
- Echo: turns the Cathedral into a versatile two second digital delay6
Presets and MIDI
Each of the eight modes holds one preset, so you can save and load up to eight presets in total6. The pedal itself has no MIDI control5. The Czech company Microdesignum fills that gap with a MIDI control module, a small electronic kit that lets you run the Cathedral from a MIDI controller or from a computer through DAW software, using Program Change or Control Change commands75.
Microdesignum offers the module in three variants5:
| Variant | Price |
|---|---|
| MIDI module to build into the effect yourself | 70.00 USD5 |
| Build-in service: they install the module in your own Cathedral | 120.00 USD5 |
| New Cathedral with the MIDI module already installed | 420.00 USD5 |
Installing the module yourself is not a plug-in job. Microdesignum's instructions call for drilling holes in the Cathedral enclosure (2mm, 3mm, 3.5mm and 16mm), soldering six points including the 9VDC, GND, encoder and Tap conductors, and screwing the module to the bottom lid7.
What reviewers said
Premier Guitar's reviewer found the Cathedral "extremely clear and precise-sounding," crediting the AD/DA converters with keeping the guitar tone smooth without digital artifacts, though noting it can be almost too clear for players who want a vintage reverb character2. The same review praised the attention to detail: "Everything from the myriad options to the 24-bit converters to the tone itself (which I will address shortly) really shows just how much attention to detail EHX put into the pedal."2 That review's clips were recorded with a 1978 Les Paul Custom into a Mesa Boogie Electra-Dyne half-stack2.
Pedal of the Day opened its review by calling the Cathedral "a beast of a reverb, with almost too many sounds and options to explain," and highlighted its true stereo I/O, ultra low noise and transparent signal path, and studio quality 24-bit converters6. MusicRadar gave the pedal an early First Look when it was new, in November 2009, listing the same core feature set of 24-bit converters, true stereo I/O, eight programmable styles, tap tempo pre-delay and the hold-for-infinite-reverb function8.
Where it sits in the EHX reverb line
The Cathedral's mode list ties it directly to the Holy Grail line: among its eight reverb styles are Grail Spring, the spring reverb taken from the Holy Grail, and Grail Flerb, alongside a second spring mode based on an Accutronics spring tank emulation25. The rest of the lineup covers Hall, Room, Plate, Reverse and Echo, the last of which turns the pedal into a two second digital delay16. That mix of inherited Holy Grail sounds and new modes is what places the Cathedral as the larger, more adjustable sibling in Electro-Harmonix's reverb offerings, with tap tempo setting the pre-delay section and holding it for infinite reverb2.
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Questions
Is the EHX Cathedral discontinued?
Yes. Electro-Harmonix lists the Cathedral as discontinued in 2020, so it is no longer made. It remains available secondhand, and a third party, Microdesignum, sells a MIDI conversion module for it, including a build-in service for pedals sent to them and a new Cathedral with the module already installed.
Does the Cathedral have an infinite reverb mode?
Yes. Holding the tap tempo footswitch engages infinite reverb, which freezes the effect so it sustains indefinitely. MusicRadar's reviewer praised this mode for sustained synth pad-esque sounds, and it works alongside the tap tempo function that sets the pre-delay section.
What is the Grail Flerb mode on the Cathedral?
Grail Flerb is one of the Cathedral's eight reverb styles. Pedal of the Day describes it as the Holy Grail Flerb from Electro-Harmonix's earlier Holy Grail series, but with greater adjustability in the Cathedral. It sits alongside Grail Spring, Accu Spring, Hall, Room, Plate, Reverse and Echo modes.
Can you save presets on the EHX Cathedral?
Yes. The Cathedral has eight programmable reverb styles with the ability to load and save, which works out to one preset for each of the different modes. Premier Guitar's reviewer called the preset system and tap tempo mode intuitive in use.
Is the Cathedral stereo?
Yes. The Cathedral has true stereo inputs and outputs, along with an ultra low noise and transparent signal path and studio quality 24-bit A/D and D/A converters, according to Pedal of the Day's review.
Does the Electro-Harmonix Cathedral have MIDI?
No. The pedal has no MIDI control of its own. Microdesignum, a third party, makes an electronic kit that adds MIDI control via Program Change or Control Change commands, driven from a foot MIDI controller or from a computer through DAW software.
Sources (8)
- Cathedral, Electro-Harmonix
- Electro-Harmonix Cathedral Stereo Reverb Pedal Review, Premier Guitar, 2010-01-08
- Electro-Harmonix Expands Reverb Line with Holy Grail Neo, Guitar Interactive Magazine, 2015-03-18
- Electro-Harmonix Freeze Sound Retainer review, MusicRadar, 2010-10-21
- MIDI Control for Electro Harmonix Cathedral Stereo Reverb, Microdesignum
- Electro-Harmonix Cathedral Stereo Reverb, Pedal of the Day, 2016-04-05
- MIDI control module for EHX Cathedral Stereo Reverb, Microdesignum, 2016-05-23
- FIRST LOOK: Electro-Harmonix Cathedral Stereo Reverb, MusicRadar, 2009-11-13
